{"id":3674,"date":"2025-04-10T14:43:36","date_gmt":"2025-04-10T05:43:36","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=3674"},"modified":"2025-04-10T14:43:38","modified_gmt":"2025-04-10T05:43:38","slug":"php-intval-%e5%ae%8c%e5%85%a8%e3%83%9e%e3%82%b9%e3%82%bf%e3%83%bc%e3%82%ac%e3%82%a4%e3%83%89%ef%bc%817%e3%81%a4%e3%81%ae%e5%bc%b7%e5%8a%9b%e3%81%aa%e6%95%b4%e6%95%b0%e5%a4%89%e6%8f%9b%e3%83%86","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=3674","title":{"rendered":"PHP intval(): \u5b8c\u5168\u30de\u30b9\u30bf\u30fc\u30ac\u30a4\u30c9\uff017\u3064\u306e\u5f37\u529b\u306a\u6574\u6570\u5909\u63db\u30c6\u30af\u30cb\u30c3\u30af"},"content":{"rendered":"\n<div class=\"toc\"><br \/>\n<b>Warning<\/b>:  Undefined array key \"is_admin\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>116<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_category_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>121<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>128<\/b><br \/>\n    <div id=\"toc_container\" class=\"sgb-toc--bullets js-smooth-scroll\" data-dialog-title=\"\u76ee\u6b21\">\n      <p class=\"toc_title\">\u76ee\u6b21 <\/p>\n      <ul class=\"toc_list\">  <li class=\"first\">    <a href=\"#i-0\">PHP intval()\u3068\u306f\uff1f\u57fa\u672c\u304b\u3089\u7406\u89e3\u3059\u308b\u6574\u6570\u5909\u63db\u306e\u4ed5\u7d44\u307f<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">intval()\u306e\u57fa\u672c\u7684\u306a\u5f79\u5272\u3068\u6a5f\u80fd\u3092\u521d\u5fc3\u8005\u306b\u3082\u308f\u304b\u308a\u3084\u3059\u304f\u89e3\u8aac<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-2\">\u6b63\u78ba\u306a\u69cb\u6587\u3068\u5f15\u6570\u306e\u4ed5\u69d8 \u2013 \u7b2c\u4e8c\u5f15\u6570\u306e\u57fa\u6570\u6307\u5b9a\u306e\u5a01\u529b<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-3\">\u306a\u305cPHP\u958b\u767a\u3067\u6574\u6570\u5909\u63db\u304c\u91cd\u8981\u306a\u306e\u304b\uff1f<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-4\">\u578b\u306e\u4e0d\u4e00\u81f4\u306b\u3088\u308b\u30d0\u30b0\u3092\u672a\u7136\u306b\u9632\u3050intval()\u306e\u4fa1\u5024<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-5\">\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\u3092\u8efd\u6e1b\u3059\u308b\u305f\u3081\u306e\u6b63\u3057\u3044\u30c7\u30fc\u30bf\u578b\u5909\u63db<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-6\">intval()\u306e7\u3064\u306e\u5b9f\u8df5\u7684\u306a\u4f7f\u7528\u30b7\u30fc\u30f3<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-7\">\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u5024\u306e\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li>        <a href=\"#i-8\">\u6587\u5b57\u5217\u5185\u306e\u6570\u5024\u3092\u62bd\u51fa\u3059\u308b\u969b\u306e\u6d3b\u7528\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-9\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5024\u306e\u578b\u4fdd\u8a3c\u306b\u5f79\u7acb\u3064\u30b1\u30fc\u30b9<\/a>      <\/li>      <li>        <a href=\"#i-10\">\u7570\u306a\u308b\u57fa\u6570\u3067\u306e\u6570\u5024\u89e3\u91c8 \u2013 2\u9032\u6570\u30fb8\u9032\u6570\u30fb16\u9032\u6570\u5bfe\u5fdc<\/a>      <\/li>      <li>        <a href=\"#i-11\">\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u969b\u306e\u6ce8\u610f\u70b9<\/a>      <\/li>      <li>        <a href=\"#i-12\">\u914d\u5217\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308bintval()\u306e\u6319\u52d5\u3068\u5bfe\u51e6\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-13\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6570\u5024\u51e6\u7406\u306b\u304a\u3051\u308b\u5b9f\u88c5\u4f8b<\/a>      <\/li>      <li>        <a href=\"#i-14\">\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u5024\u306e\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li>        <a href=\"#i-15\">\u6587\u5b57\u5217\u5185\u306e\u6570\u5024\u3092\u62bd\u51fa\u3059\u308b\u969b\u306e\u6d3b\u7528\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-16\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5024\u306e\u578b\u4fdd\u8a3c\u306b\u5f79\u7acb\u3064\u30b1\u30fc\u30b9<\/a>      <\/li>      <li>        <a href=\"#i-17\">\u7570\u306a\u308b\u57fa\u6570\u3067\u306e\u6570\u5024\u89e3\u91c8 \u2013 2\u9032\u6570\u30fb8\u9032\u6570\u30fb16\u9032\u6570\u5bfe\u5fdc<\/a>      <\/li>      <li>        <a href=\"#i-18\">\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u969b\u306e\u6ce8\u610f\u70b9<\/a>      <\/li>      <li>        <a href=\"#i-19\">\u914d\u5217\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308bintval()\u306e\u6319\u52d5\u3068\u5bfe\u51e6\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-20\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6570\u5024\u51e6\u7406\u306b\u304a\u3051\u308b\u5b9f\u88c5\u4f8b<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-21\">intval() vs (int)\u30ad\u30e3\u30b9\u30c8 \u2013 \u77e5\u3063\u3066\u304a\u304f\u3079\u304d\u91cd\u8981\u306a\u9055\u3044<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-22\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6bd4\u8f03 \u2013 \u3069\u3061\u3089\u304c\u9ad8\u901f\u3067\u30ea\u30bd\u30fc\u30b9\u52b9\u7387\u304c\u826f\u3044\u306e\u304b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-23\">\u578b\u5909\u63db\u306e\u6319\u52d5\u306e\u9055\u3044\u3068\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u3067\u306e\u7d50\u679c\u306e\u5dee\u7570<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-24\">intval()\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-25\">\u4e0d\u5fc5\u8981\u306a\u578b\u5909\u63db\u3092\u907f\u3051\u308b\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u30d1\u30bf\u30fc\u30f3<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-26\">\u5927\u898f\u6a21\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306e\u52b9\u7387\u7684\u306a\u6574\u6570\u5909\u63db\u6226\u7565<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-27\">intval()\u3067\u767a\u751f\u3057\u304c\u3061\u306a5\u3064\u306e\u843d\u3068\u3057\u7a74\u3068\u89e3\u6c7a\u7b56<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-28\">32\u30d3\u30c3\u30c8\u74b0\u5883\u306864\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306e\u6319\u52d5\u306e\u9055\u3044\u306b\u6ce8\u610f<\/a>      <\/li>      <li>        <a href=\"#i-29\">\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3092\u9632\u3050\u305f\u3081\u306e\u5bfe\u7b56\u3068\u4ee3\u66ff\u30a2\u30d7\u30ed\u30fc\u30c1<\/a>      <\/li>      <li>        <a href=\"#i-30\">NULL\u3084\u7a7a\u6587\u5b57\u5217\u306b\u5bfe\u3059\u308b\u4e88\u671f\u305b\u306c\u5909\u63db\u7d50\u679c\u3078\u306e\u5bfe\u51e6\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-31\">\u56fd\u969b\u5316\u5bfe\u5fdc\u6642\u306e\u6570\u5024\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306b\u3088\u308b\u554f\u984c\u3068\u89e3\u6c7a\u7b56<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-32\">\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u4e0d\u8db3\u306b\u3088\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30db\u30fc\u30eb\u306e\u9632\u6b62\u65b9\u6cd5<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-33\">\u5b9f\u52d9\u3067\u4f7f\u3048\u308b\uff01intval()\u3092\u6d3b\u7528\u3057\u305f\u5b9f\u88c5\u30b5\u30f3\u30d7\u30eb\u96c6<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-34\">\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\u3067\u306e\u5b89\u5168\u306a\u30d1\u30e9\u30e1\u30fc\u30bf\u53d6\u5f97\u30b3\u30fc\u30c9<\/a>      <\/li>      <li>        <a href=\"#i-35\">\u5546\u54c1\u6570\u91cf\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u30b5\u30cb\u30bf\u30a4\u30ba\u306e\u5b9f\u88c5\u4f8b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-36\">ID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u306b\u304a\u3051\u308b\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30d1\u30bf\u30fc\u30f3<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-37\">PHP 8\u4ee5\u964d\u306eintval()\u306e\u5909\u66f4\u70b9\u3068\u4e92\u63db\u6027\u3078\u306e\u5f71\u97ff<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-38\">\u6700\u65b0\u30d0\u30fc\u30b8\u30e7\u30f3\u3067\u306e\u4ed5\u69d8\u5909\u66f4\u3068\u5f8c\u65b9\u4e92\u63db\u6027\u306b\u3064\u3044\u3066<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-39\">PHP 8\u306e\u53b3\u683c\u306a\u578b\u30c1\u30a7\u30c3\u30af\u306b\u5bfe\u5fdc\u3059\u308bintval()\u306e\u4f7f\u3044\u65b9<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-40\">\u307e\u3068\u3081\uff1a\u5b89\u5168\u3067\u52b9\u7387\u7684\u306aintval()\u306e\u4f7f\u3044\u65b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-41\">\u3053\u306e\u8a18\u4e8b\u3067\u5b66\u3093\u30607\u3064\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u5b9f\u8df5\u3059\u308b\u305f\u3081\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-49\">\u4eca\u65e5\u304b\u3089\u5c0e\u5165\u3067\u304d\u308bintval()\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>      <\/li>    <\/ul>  <\/li><\/ul>\n      <a href=\"#\" class=\"sgb-toc-button js-toc-button\" rel=\"nofollow\" data-open-dialog=\"true\"><i class=\"fa fa-list\"><\/i><span class=\"sgb-toc-button__text\">\u76ee\u6b21\u3078<\/span><\/a>\n    <\/div><\/div><h2 class=\"wp-block-heading\" id=\"i-0\">PHP intval()\u3068\u306f\uff1f\u57fa\u672c\u304b\u3089\u7406\u89e3\u3059\u308b\u6574\u6570\u5909\u63db\u306e\u4ed5\u7d44\u307f<\/h2>\n\n\n\n<p>PHP\u3067\u30a6\u30a7\u30d6\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u958b\u767a\u3057\u3066\u3044\u308b\u3068\u3001\u69d8\u3005\u306a\u30c7\u30fc\u30bf\u578b\u306e\u5909\u63db\u304c\u5fc5\u8981\u306b\u306a\u308a\u307e\u3059\u3002\u7279\u306b\u30d5\u30a9\u30fc\u30e0\u304b\u3089\u306e\u5165\u529b\u5024\u3084\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u5024\u3092\u6271\u3046\u969b\u3001\u6574\u6570\u578b\u3078\u306e\u5909\u63db\u306f\u983b\u7e41\u306b\u767a\u751f\u3059\u308b\u51e6\u7406\u3067\u3059\u3002\u305d\u3093\u306a\u6642\u306b\u5f37\u529b\u306a\u5473\u65b9\u3068\u306a\u308b\u306e\u304c<code>intval()<\/code>\u95a2\u6570\u3067\u3059\u3002<\/p>\n\n\n\n<p><code>intval()<\/code>\u306fPHP\u306e\u7d44\u307f\u8fbc\u307f\u95a2\u6570\u3067\u3001\u305d\u306e\u540d\u524d\u304c\u793a\u3059\u901a\u308a\u300cinteger value\uff08\u6574\u6570\u5024\uff09\u300d\u3092\u53d6\u5f97\u3059\u308b\u305f\u3081\u306e\u95a2\u6570\u3067\u3059\u3002\u5358\u7d14\u305d\u3046\u306b\u898b\u3048\u308b\u3053\u306e\u95a2\u6570\u306f\u3001\u5b9f\u306fPHP\u958b\u767a\u306b\u304a\u3044\u3066\u975e\u5e38\u306b\u91cd\u8981\u306a\u5f79\u5272\u3092\u62c5\u3063\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u3053\u306e\u95a2\u6570\u306e\u6700\u5927\u306e\u7279\u5fb4\u306f\u3001<strong>\u3042\u3089\u3086\u308b\u578b\u306e\u5909\u6570\u304b\u3089\u6574\u6570\u5024\u3092\u62bd\u51fa\u3067\u304d\u308b<\/strong>\u3068\u3044\u3046\u70b9\u3067\u3059\u3002\u6587\u5b57\u5217\u3001\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3001\u30d6\u30fc\u30eb\u5024\u3001\u3055\u3089\u306b\u306f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3084\u914d\u5217\u307e\u3067\u3001\u69d8\u3005\u306a\u5909\u6570\u578b\u304b\u3089\u305d\u306e\u6574\u6570\u7684\u306a\u5024\u3092\u53d6\u308a\u51fa\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\n$result1 = intval(42);        \/\/ 42\uff08\u6574\u6570\u3092\u305d\u306e\u307e\u307e\u8fd4\u3059\uff09\n$result2 = intval(\"42\");      \/\/ 42\uff08\u6587\u5b57\u5217\u304b\u3089\u6574\u6570\u3092\u62bd\u51fa\uff09\n$result3 = intval(42.8);      \/\/ 42\uff08\u5c0f\u6570\u70b9\u4ee5\u4e0b\u3092\u5207\u308a\u6368\u3066\uff09\n$result4 = intval(true);      \/\/ 1\uff08\u771f\u507d\u5024\u3092\u6574\u6570\u306b\u5909\u63db\uff09\n<\/pre>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u7279\u306b\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u5024\u306e\u51e6\u7406\u3084\u3001\u7570\u306a\u308b\u30b7\u30b9\u30c6\u30e0\u9593\u3067\u30c7\u30fc\u30bf\u3092\u3084\u308a\u53d6\u308a\u3059\u308b\u969b\u306b\u5f79\u7acb\u3061\u307e\u3059\u3002\u4f8b\u3048\u3070\u3001URL\u30d1\u30e9\u30e1\u30fc\u30bf\u3084\u5165\u529b\u30d5\u30a9\u30fc\u30e0\u304b\u3089\u306e\u30c7\u30fc\u30bf\u306f\u57fa\u672c\u7684\u306b\u6587\u5b57\u5217\u3068\u3057\u3066\u6271\u308f\u308c\u307e\u3059\u304c\u3001\u3053\u308c\u3089\u3092\u6570\u5024\u8a08\u7b97\u306b\u4f7f\u7528\u3059\u308b\u306b\u306f\u9069\u5207\u306a\u578b\u5909\u63db\u304c\u4e0d\u53ef\u6b20\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u307e\u305f\u3001PHP\u306f\u300c\u3086\u308b\u3044\u578b\u4ed8\u3051\u300d\u306e\u8a00\u8a9e\u3068\u3057\u3066\u77e5\u3089\u308c\u3066\u3044\u307e\u3059\u304c\u3001\u3060\u304b\u3089\u3053\u305d\u610f\u56f3\u7684\u306b\u578b\u3092\u5236\u5fa1\u3059\u308b\u5fc5\u8981\u6027\u304c\u9ad8\u304f\u3001<code>intval()<\/code>\u306f\u305d\u306e\u305f\u3081\u306e\u91cd\u8981\u306a\u30c4\u30fc\u30eb\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">intval()\u306e\u57fa\u672c\u7684\u306a\u5f79\u5272\u3068\u6a5f\u80fd\u3092\u521d\u5fc3\u8005\u306b\u3082\u308f\u304b\u308a\u3084\u3059\u304f\u89e3\u8aac<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u3001\u30b7\u30f3\u30d7\u30eb\u306a\u304c\u3089\u3082\u975e\u5e38\u306b\u5f37\u529b\u306a\u6a5f\u80fd\u3092\u6301\u3063\u3066\u3044\u307e\u3059\u3002\u305d\u306e\u57fa\u672c\u7684\u306a\u5f79\u5272\u306f**\u300c\u3069\u3093\u306a\u5024\u3067\u3082\u6574\u6570\u3068\u3057\u3066\u89e3\u91c8\u3059\u308b\u300d**\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u521d\u3081\u3066PHP\u3092\u5b66\u3076\u65b9\u306b\u3068\u3063\u3066\u3001\u30c7\u30fc\u30bf\u578b\u306e\u6982\u5ff5\u306f\u5c11\u3057\u8907\u96d1\u306b\u611f\u3058\u308b\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002PHP\u3067\u306f\u30e6\u30fc\u30b6\u30fc\u304b\u3089\u306e\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u3084URL\u30d1\u30e9\u30e1\u30fc\u30bf\u306a\u3069\u3001\u591a\u304f\u306e\u30c7\u30fc\u30bf\u304c\u300c\u6587\u5b57\u5217\u300d\u3068\u3057\u3066\u53d6\u5f97\u3055\u308c\u307e\u3059\u3002\u4f8b\u3048\u3070\u3001\u30d5\u30a9\u30fc\u30e0\u3067\u6570\u91cf\u300c5\u300d\u3092\u5165\u529b\u3057\u3066\u3082\u3001PHP\u306f\u305d\u308c\u3092\u6587\u5b57\u5217\u306e\u201d5\u2033\u3068\u3057\u3066\u53d7\u3051\u53d6\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u3057\u304b\u3057\u3001\u8a08\u7b97\u3092\u884c\u3046\u305f\u3081\u306b\u306f\u6587\u5b57\u5217\u3067\u306f\u306a\u304f\u6570\u5024\u3068\u3057\u3066\u6271\u3046\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u3053\u3067<code>intval()<\/code>\u306e\u51fa\u756a\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30d5\u30a9\u30fc\u30e0\u304b\u3089\u53d7\u3051\u53d6\u3063\u305f\u5546\u54c1\u6570\u91cf\uff08\u6587\u5b57\u5217\uff09\n$quantity = $_POST['quantity']; \/\/ \"5\"\n\n\/\/ \u3053\u306e\u307e\u307e\u3067\u306f\u8a08\u7b97\u3067\u304d\u306a\u3044\n$total = $quantity * 1200; \/\/ \u6587\u5b57\u5217\u3068\u6570\u5024\u306e\u4e57\u7b97\n\n\/\/ intval()\u3067\u6574\u6570\u306b\u5909\u63db\u3057\u3066\u304b\u3089\u8a08\u7b97\n$quantity = intval($_POST['quantity']); \/\/ 5\uff08\u6574\u6570\uff09\n$total = $quantity * 1200; \/\/ \u6b63\u3057\u304f\u8a08\u7b97\u3067\u304d\u308b\n<\/pre>\n\n\n\n<p><code>intval()<\/code>\u306f\u69d8\u3005\u306a\u30c7\u30fc\u30bf\u578b\u306b\u5bfe\u3057\u3066\u4e00\u8cab\u3057\u305f\u52d5\u4f5c\u3092\u3057\u307e\u3059\uff1a<\/p>\n\n\n<div id=\"id-ff718f0a-00c4-4538-9e79-a5996a99e44b\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u5165\u529b\u5024<\/th><th>intval()\u306e\u7d50\u679c<\/th><th>\u89e3\u8aac<\/th><\/tr><\/thead><tbody><tr><td>42<\/td><td>42<\/td><td>\u6574\u6570\u306f\u305d\u306e\u307e\u307e<\/td><\/tr><tr><td>\u201c42\u201d<\/td><td>42<\/td><td>\u6587\u5b57\u5217\u304b\u3089\u6574\u6570\u306b\u5909\u63db<\/td><\/tr><tr><td>\u201c42abc\u201d<\/td><td>42<\/td><td>\u5148\u982d\u306e\u6570\u5b57\u90e8\u5206\u306e\u307f\u62bd\u51fa<\/td><\/tr><tr><td>\u201cabc42\u201d<\/td><td>0<\/td><td>\u5148\u982d\u304c\u6570\u5b57\u3067\u306a\u3044\u305f\u30810<\/td><\/tr><tr><td>42.8<\/td><td>42<\/td><td>\u5c0f\u6570\u70b9\u4ee5\u4e0b\u3092\u5207\u308a\u6368\u3066<\/td><\/tr><tr><td>true<\/td><td>1<\/td><td>\u771f\u5024\u306f1<\/td><\/tr><tr><td>false<\/td><td>0<\/td><td>\u507d\u5024\u306f0<\/td><\/tr><tr><td>null<\/td><td>0<\/td><td>null\u306f0<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u7279\u306b\u6ce8\u610f\u3059\u3079\u304d\u306f\u6587\u5b57\u5217\u306e\u6271\u3044\u3067\u3059\u3002<code>intval()<\/code>\u306f\u6587\u5b57\u5217\u306e\u5148\u982d\u304b\u3089\u6570\u5b57\u3068\u3057\u3066\u89e3\u91c8\u3067\u304d\u308b\u90e8\u5206\u3060\u3051\u3092\u8fd4\u3057\u3001\u6570\u5b57\u4ee5\u5916\u306e\u6587\u5b57\u306b\u5230\u9054\u3057\u305f\u6642\u70b9\u3067\u5909\u63db\u3092\u7d42\u4e86\u3057\u307e\u3059\u3002\u3053\u308c\u306f\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u3057\u3066\u306f\u4e0d\u5341\u5206\u306a\u5834\u5408\u304c\u3042\u308b\u305f\u3081\u3001\u3088\u308a\u53b3\u5bc6\u306a\u691c\u8a3c\u304c\u5fc5\u8981\u306a\u5834\u9762\u3067\u306f<code>is_numeric()<\/code>\u306a\u3069\u3068\u7d44\u307f\u5408\u308f\u305b\u3066\u4f7f\u3046\u3053\u3068\u3092\u304a\u52e7\u3081\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-2\">\u6b63\u78ba\u306a\u69cb\u6587\u3068\u5f15\u6570\u306e\u4ed5\u69d8 \u2013 \u7b2c\u4e8c\u5f15\u6570\u306e\u57fa\u6570\u6307\u5b9a\u306e\u5a01\u529b<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306e\u771f\u306e\u529b\u3092\u767a\u63ee\u3059\u308b\u306e\u306f\u3001\u305d\u306e\u67d4\u8edf\u306a\u5f15\u6570\u4ed5\u69d8\u306b\u3042\u308a\u307e\u3059\u3002\u516c\u5f0f\u306a\u69cb\u6587\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">int intval ( mixed $var [, int $base = 10 ] )\n<\/pre>\n\n\n\n<p>\u3053\u306e\u95a2\u6570\u306f2\u3064\u306e\u5f15\u6570\u3092\u53d7\u3051\u53d6\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>$var<\/strong> (\u5fc5\u9808): \u5909\u63db\u3057\u305f\u3044\u5909\u6570\uff08\u4efb\u610f\u306e\u578b\uff09<\/li>\n\n\n\n<li><strong>$base<\/strong> (\u30aa\u30d7\u30b7\u30e7\u30f3): \u5909\u63db\u306e\u57fa\u6570\uff08\u30c7\u30d5\u30a9\u30eb\u30c8\u306f10\uff09<\/li>\n<\/ol>\n\n\n\n<p>\u7279\u306b\u6ce8\u76ee\u3059\u3079\u304d\u306f\u7b2c\u4e8c\u5f15\u6570\u306e<code>$base<\/code>\u30d1\u30e9\u30e1\u30fc\u30bf\u3067\u3059\u3002\u3053\u306e\u5f15\u6570\u306f2\u304b\u308936\u307e\u3067\u306e\u6574\u6570\u3092\u6307\u5b9a\u3067\u304d\u3001<strong>\u7570\u306a\u308b\u9032\u6570\u8868\u8a18\u306e\u6587\u5b57\u5217\u309210\u9032\u6570\u306e\u6574\u6570\u306b\u5909\u63db<\/strong>\u3059\u308b\u969b\u306b\u4f7f\u7528\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u69d8\u3005\u306a\u57fa\u6570\u3067\u306e\u5909\u63db\u4f8b\necho intval(\"1010\", 2);    \/\/ \u7d50\u679c: 10 (2\u9032\u6570\u306e1010)\necho intval(\"12\", 8);      \/\/ \u7d50\u679c: 10 (8\u9032\u6570\u306e12)\necho intval(\"A\", 16);      \/\/ \u7d50\u679c: 10 (16\u9032\u6570\u306eA)\necho intval(\"FF\", 16);     \/\/ \u7d50\u679c: 255 (16\u9032\u6570\u306eFF)\necho intval(\"10\", 36);     \/\/ \u7d50\u679c: 36 (36\u9032\u6570\u306e10)\n<\/pre>\n\n\n\n<p>\u3053\u306e\u57fa\u6570\u6307\u5b9a\u6a5f\u80fd\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u5b9f\u8df5\u7684\u306a\u30b7\u30fc\u30f3\u3067\u975e\u5e38\u306b\u5f79\u7acb\u3061\u307e\u3059\uff1a<\/p>\n\n\n<div id=\"id-4eebd30d-19f6-419a-953c-3aca87be2062\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u4f7f\u7528\u30b7\u30fc\u30f3<\/th><th>\u30b3\u30fc\u30c9\u4f8b<\/th><th>\u8aac\u660e<\/th><\/tr><\/thead><tbody><tr><td>\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u5909\u63db<\/td><td><code>$r = intval(substr(\"#FF5733\", 1, 2), 16);<\/code><\/td><td>HTML\u306e\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u3092RGB\u5024\u306b\u5909\u63db<\/td><\/tr><tr><td>16\u9032\u6570IP\u5909\u63db<\/td><td><code>$dec = intval(\"C0A80101\", 16);<\/code><\/td><td>16\u9032\u6570\u8868\u8a18\u306eIP\u30a2\u30c9\u30ec\u30b9\u309210\u9032\u6570\u306b\u5909\u63db<\/td><\/tr><tr><td>\u30d0\u30a4\u30ca\u30ea\u30c7\u30fc\u30bf\u51e6\u7406<\/td><td><code>$value = intval(\"1101\", 2);<\/code><\/td><td>\u30d0\u30a4\u30ca\u30ea\u30c7\u30fc\u30bf\u309210\u9032\u6570\u306b\u5909\u63db<\/td><\/tr><tr><td>\u7279\u6b8a\u306a\u8a18\u6570\u6cd5\u51e6\u7406<\/td><td><code>$value = intval(\"XYZ\", 36);<\/code><\/td><td>\u62e1\u5f35\u30a2\u30eb\u30d5\u30a1\u30d9\u30c3\u30c8\u8a18\u6570\u6cd5\u306e\u51e6\u7406<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u6ce8\u610f\u3059\u3079\u304d\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\u304c\u3044\u304f\u3064\u304b\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u57fa\u6570\u6307\u5b9a\u306f\u6587\u5b57\u5217\u306b\u5bfe\u3057\u3066\u306e\u307f\u6709\u52b9<\/strong>\u3067\u3059\u3002\u6574\u6570\u3084\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u306b\u57fa\u6570\u3092\u6307\u5b9a\u3057\u3066\u3082\u7121\u8996\u3055\u308c\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u57fa\u6570\u306f<strong>2\u304b\u308936\u306e\u7bc4\u56f2<\/strong>\u3067\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u7bc4\u56f2\u5916\u306e\u5024\u3092\u6307\u5b9a\u3059\u308b\u3068\u3001\u57fa\u657010\u3068\u3057\u3066\u51e6\u7406\u3055\u308c\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u6587\u5b57\u5217\u304c\u6307\u5b9a\u3057\u305f\u57fa\u6570\u306e\u6709\u52b9\u306a\u6570\u5b57\u3067\u59cb\u307e\u3063\u3066\u3044\u306a\u3044\u5834\u5408\u3001\u7d50\u679c\u306f0\u306b\u306a\u308a\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u30a2\u30eb\u30d5\u30a1\u30d9\u30c3\u30c8\u306e\u5927\u6587\u5b57\u3068\u5c0f\u6587\u5b57\u306f\u533a\u5225\u3055\u308c\u307e\u305b\u3093\uff08\u201dFF\u201d = \u201cff\u201d\uff09\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u306e\u57fa\u6570\u6307\u5b9a\u6a5f\u80fd\u3092\u4f7f\u3044\u3053\u306a\u3059\u3053\u3068\u3067\u300116\u9032\u6570\u306e\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u5909\u63db\u3001\u30d0\u30a4\u30ca\u30ea\u30c7\u30fc\u30bf\u306e\u51e6\u7406\u3001\u6697\u53f7\u5316\u6587\u5b57\u5217\u306e\u89e3\u8aad\u306a\u3069\u3001\u69d8\u3005\u306a\u9ad8\u5ea6\u306a\u30c7\u30fc\u30bf\u51e6\u7406\u3092\u7c21\u6f54\u306b\u5b9f\u88c5\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-3\">\u306a\u305cPHP\u958b\u767a\u3067\u6574\u6570\u5909\u63db\u304c\u91cd\u8981\u306a\u306e\u304b\uff1f<\/h2>\n\n\n\n<p>PHP\u306f\u30a6\u30a7\u30d6\u958b\u767a\u306b\u304a\u3044\u3066\u5e83\u304f\u4f7f\u308f\u308c\u3066\u3044\u308b\u8a00\u8a9e\u3067\u3059\u304c\u3001\u305d\u306e\u67d4\u8edf\u6027\u304c\u6642\u306b\u843d\u3068\u3057\u7a74\u306b\u306a\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u7279\u306b\u300c\u578b\u300d\u306b\u95a2\u3059\u308b\u67d4\u8edf\u6027\u306f\u3001\u4fbf\u5229\u306a\u53cd\u9762\u3001\u4e88\u671f\u305b\u306c\u30d0\u30b0\u3084\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u554f\u984c\u306e\u539f\u56e0\u306b\u306a\u308a\u5f97\u307e\u3059\u3002<\/p>\n\n\n\n<p>PHP\u306f<strong>\u5f31\u3044\u578b\u4ed8\u3051\u8a00\u8a9e<\/strong>\u3067\u3042\u308a\u3001\u5909\u6570\u306e\u578b\u304c\u81ea\u52d5\u7684\u306b\u5909\u63db\u3055\u308c\u308b\u6027\u8cea\u304c\u3042\u308a\u307e\u3059\u3002\u4f8b\u3048\u3070\u3001\u6587\u5b57\u5217\u306e \u201c5\u201d \u3068\u6570\u5024\u306e 5 \u3092\u6bd4\u8f03\u3059\u308b\u3068\u3001PHP\u306f\u81ea\u52d5\u7684\u306b\u578b\u5909\u63db\u3092\u884c\u3044\u3001\u4e21\u8005\u304c\u7b49\u3057\u3044\u3068\u5224\u65ad\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$a = \"5\";   \/\/ \u6587\u5b57\u5217\n$b = 5;     \/\/ \u6574\u6570\nvar_dump($a == $b);  \/\/ bool(true) - \u7de9\u3044\u6bd4\u8f03\u3067\u306f\u578b\u304c\u7570\u306a\u3063\u3066\u3082\u7b49\u3057\u3044\u3068\u5224\u65ad\nvar_dump($a === $b); \/\/ bool(false) - \u53b3\u5bc6\u306a\u6bd4\u8f03\u3067\u306f\u578b\u306e\u9055\u3044\u3082\u8003\u616e\u3055\u308c\u308b\n<\/pre>\n\n\n\n<p>\u3053\u306e\u81ea\u52d5\u5909\u63db\u6a5f\u80fd\u306f\u958b\u767a\u306e\u624b\u9593\u3092\u7701\u3051\u308b\u30e1\u30ea\u30c3\u30c8\u304c\u3042\u308a\u307e\u3059\u304c\u3001\u540c\u6642\u306b\u4e88\u6e2c\u3067\u304d\u306a\u3044\u52d5\u4f5c\u3092\u5f15\u304d\u8d77\u3053\u3059\u53ef\u80fd\u6027\u3082\u3042\u308a\u307e\u3059\u3002\u7279\u306b\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3084\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5024\u3092\u51e6\u7406\u3059\u308b\u969b\u306b\u306f\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u4f8b\u3048\u3070\u3001\u30e6\u30fc\u30b6\u30fcID\u3092\u4f7f\u3063\u3066\u7279\u5b9a\u306e\u30e6\u30fc\u30b6\u30fc\u60c5\u5831\u3092\u53d6\u5f97\u3059\u308b\u51e6\u7406\u3092\u8003\u3048\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5371\u967a\u306a\u4f8b\n$user_id = $_GET['id']; \/\/ '42' \u3084 '42abc' \u306a\u3069\u306e\u6587\u5b57\u5217\u304b\u3082\u3057\u308c\u306a\u3044\n$query = \"SELECT * FROM users WHERE id = $user_id\";\n\/\/ $user_id\u304c\u6570\u5024\u3067\u306a\u3044\u5834\u5408\u3001SQL\u30a8\u30e9\u30fc\u3084\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306e\u53ef\u80fd\u6027\n\n\/\/ \u5b89\u5168\u306a\u4f8b\n$user_id = intval($_GET['id']); \/\/ \u78ba\u5b9f\u306b\u6574\u6570\u306b\u5909\u63db\n$query = \"SELECT * FROM users WHERE id = $user_id\";\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306b\u3001<code>intval()<\/code>\u3092\u4f7f\u3063\u3066\u660e\u793a\u7684\u306b\u6574\u6570\u5909\u63db\u3059\u308b\u3053\u3068\u3067\u3001\u4ee5\u4e0b\u306e\u30e1\u30ea\u30c3\u30c8\u304c\u5f97\u3089\u308c\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30b3\u30fc\u30c9\u306e\u610f\u56f3\u304c\u660e\u78ba\u306b\u306a\u308b<\/strong> \u2013 \u300c\u3053\u306e\u5909\u6570\u306f\u6574\u6570\u3068\u3057\u3066\u6271\u3044\u305f\u3044\u300d\u3068\u3044\u3046\u610f\u56f3\u304c\u4ed6\u306e\u958b\u767a\u8005\u306b\u3082\u4f1d\u308f\u308a\u307e\u3059<\/li>\n\n\n\n<li><strong>\u4e88\u6e2c\u53ef\u80fd\u306a\u52d5\u4f5c<\/strong> \u2013 \u81ea\u52d5\u578b\u5909\u63db\u306b\u983c\u3089\u305a\u3001\u5e38\u306b\u4e00\u8cab\u3057\u305f\u7d50\u679c\u304c\u5f97\u3089\u308c\u307e\u3059<\/li>\n\n\n\n<li><strong>\u30d0\u30b0\u306e\u4e88\u9632<\/strong> \u2013 \u578b\u306e\u4e0d\u4e00\u81f4\u306b\u3088\u308b\u30a8\u30e9\u30fc\u3084\u30d0\u30b0\u3092\u672a\u7136\u306b\u9632\u304e\u307e\u3059<\/li>\n\n\n\n<li><strong>\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u306e\u5411\u4e0a<\/strong> \u2013 \u7279\u306b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u3084\u30d5\u30a1\u30a4\u30eb\u64cd\u4f5c\u306a\u3069\u3067\u5b89\u5168\u6027\u304c\u9ad8\u307e\u308a\u307e\u3059<\/li>\n<\/ol>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306f\u3001\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u3001URL\u30d1\u30e9\u30e1\u30fc\u30bf\u3001API\u30ec\u30b9\u30dd\u30f3\u30b9\u3001\u8a2d\u5b9a\u30d5\u30a1\u30a4\u30eb\u306e\u5024\u306a\u3069\u3001\u69d8\u3005\u306a\u5834\u9762\u3067\u6570\u5024\u30c7\u30fc\u30bf\u3092\u6271\u3044\u307e\u3059\u3002\u3053\u308c\u3089\u306f\u3057\u3070\u3057\u3070\u6587\u5b57\u5217\u3068\u3057\u3066\u53d6\u5f97\u3055\u308c\u308b\u305f\u3081\u3001\u9069\u5207\u306a\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u6574\u6570\u5909\u63db\u3092\u884c\u3046\u3053\u3068\u304c\u30af\u30ea\u30fc\u30f3\u3067\u5b89\u5168\u306a\u30b3\u30fc\u30c9\u3078\u306e\u7b2c\u4e00\u6b69\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-4\">\u578b\u306e\u4e0d\u4e00\u81f4\u306b\u3088\u308b\u30d0\u30b0\u3092\u672a\u7136\u306b\u9632\u3050intval()\u306e\u4fa1\u5024<\/h3>\n\n\n\n<p>PHP\u306e\u67d4\u8edf\u306a\u578b\u30b7\u30b9\u30c6\u30e0\u306f\u4fbf\u5229\u3067\u3042\u308b\u53cd\u9762\u3001\u6c17\u3065\u304d\u306b\u304f\u3044\u30d0\u30b0\u3092\u751f\u307f\u51fa\u3059\u6e29\u5e8a\u306b\u3082\u306a\u308a\u307e\u3059\u3002\u7279\u306b\u5916\u90e8\u304b\u3089\u306e\u30c7\u30fc\u30bf\u3092\u51e6\u7406\u3059\u308b\u969b\u3001\u578b\u306e\u4e0d\u4e00\u81f4\u306f\u601d\u308f\u306c\u30a8\u30e9\u30fc\u3084\u8106\u5f31\u6027\u306e\u539f\u56e0\u306b\u306a\u308a\u304c\u3061\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u4f8b\u3048\u3070\u3001\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\u3092\u8003\u3048\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5371\u967a\u306a\u30b3\u30fc\u30c9\u4f8b\n$page = $_GET['page']; \/\/ URL\u304b\u3089\u53d6\u5f97\u3057\u305f\u30da\u30fc\u30b8\u756a\u53f7\n$items_per_page = 10;\n$offset = ($page - 1) * $items_per_page;\n\n\/\/ \u554f\u984c\u70b9:\n\/\/ - $page\u304c\u6587\u5b57\u5217\u306e\u5834\u5408\u3001\u81ea\u52d5\u7684\u306b\u6570\u5024\u5909\u63db\u304c\u8a66\u307f\u3089\u308c\u308b\n\/\/ - \"2\"\u306a\u3089\u554f\u984c\u306a\u3044\u304c\u3001\"two\"\u306e\u3088\u3046\u306a\u6587\u5b57\u5217\u3067\u306f\u30a8\u30e9\u30fc\n\/\/ - \u7a7a\u6587\u5b57\u5217\u306f0\u3068\u3057\u3066\u8a55\u4fa1\u3055\u308c\u3001\u8a08\u7b97\u7d50\u679c\u304c\u4e0d\u6b63\u78ba\u306b\u306a\u308b\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306a\u554f\u984c\u3092\u89e3\u6c7a\u3059\u308b\u305f\u3081\u3001<code>intval()<\/code>\u306b\u3088\u308b\u660e\u793a\u7684\u306a\u578b\u5909\u63db\u304c\u975e\u5e38\u306b\u4fa1\u5024\u3092\u6301\u3061\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5b89\u5168\u306a\u30b3\u30fc\u30c9\u4f8b\n$page = intval($_GET['page']);\nif ($page &lt; 1) $page = 1; \/\/ \u4e0d\u6b63\u5024\u3078\u306e\u5bfe\u7b56\n$items_per_page = 10;\n$offset = ($page - 1) * $items_per_page;\n<\/pre>\n\n\n\n<p><code>intval()<\/code>\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u5f97\u3089\u308c\u308b\u4e3b\u306a\u5229\u70b9\u306f\u6b21\u306e\u3068\u304a\u308a\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u4e88\u6e2c\u53ef\u80fd\u306a\u52d5\u4f5c<\/strong>: \u3069\u3093\u306a\u5165\u529b\u5024\u306b\u5bfe\u3057\u3066\u3082\u5e38\u306b\u6574\u6570\u5024\u3092\u8fd4\u3059\u305f\u3081\u3001\u305d\u306e\u5f8c\u306e\u51e6\u7406\u304c\u5b89\u5b9a\u3057\u307e\u3059<\/li>\n\n\n\n<li><strong>\u5883\u754c\u6761\u4ef6\u306e\u660e\u78ba\u5316<\/strong>: \u6570\u5024\u3068\u3057\u3066\u89e3\u91c8\u3067\u304d\u306a\u3044\u5165\u529b\u306f0\u306b\u306a\u308b\u305f\u3081\u3001\u7570\u5e38\u5024\u306e\u51e6\u7406\u304c\u7d71\u4e00\u3055\u308c\u307e\u3059<\/li>\n\n\n\n<li><strong>\u6697\u9ed9\u7684\u578b\u5909\u63db\u306e\u7f60\u3092\u56de\u907f<\/strong>: PHP\u306e\u7de9\u3044\u6bd4\u8f03\uff08==\uff09\u306b\u3088\u308b\u601d\u308f\u306c\u7b49\u4fa1\u5224\u5b9a\u3092\u9632\u304e\u307e\u3059<\/li>\n<\/ol>\n\n\n\n<p>\u7279\u306b\u6ce8\u610f\u3059\u3079\u304d\u306f\u3001PHP\u306e\u7de9\u3044\u6bd4\u8f03\u6f14\u7b97\u5b50\uff08==\uff09\u306b\u3088\u308b\u578b\u5909\u63db\u306e\u7f60\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$input = \"42abc\";\nif ($input == 42) { \/\/ true \u306b\u306a\u3063\u3066\u3057\u307e\u3046\uff01\n    \/\/ \u610f\u56f3\u305b\u305a\u5b9f\u884c\u3055\u308c\u308b\u51e6\u7406\n}\n\n\/\/ intval()\u3068\u53b3\u5bc6\u6bd4\u8f03\u3092\u4f7f\u3063\u305f\u5b89\u5168\u306a\u65b9\u6cd5\nif (intval($input) === 42) { \/\/ false \u306b\u306a\u308b\n    \/\/ \u9069\u5207\u306b\u51e6\u7406\u3055\u308c\u308b\n}\n<\/pre>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306f\u3001\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u51e6\u7406\u3001URL\u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u53d6\u5f97\u3001API\u3068\u306e\u9023\u643a\u306a\u3069\u3001\u69d8\u3005\u306a\u5834\u9762\u3067\u578b\u306e\u4e0d\u4e00\u81f4\u304c\u767a\u751f\u3057\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u30b7\u30ca\u30ea\u30aa\u3067<code>intval()<\/code>\u3092\u9069\u5207\u306b\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u30d0\u30b0\u306e\u767a\u751f\u7387\u3092\u5927\u5e45\u306b\u6e1b\u3089\u3057\u3001\u30b3\u30fc\u30c9\u306e\u5805\u7262\u6027\u3068\u53ef\u8aad\u6027\u3092\u5411\u4e0a\u3055\u305b\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\u3092\u8efd\u6e1b\u3059\u308b\u305f\u3081\u306e\u6b63\u3057\u3044\u30c7\u30fc\u30bf\u578b\u5909\u63db<\/h3>\n\n\n\n<p>Web\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u306b\u304a\u3044\u3066\u3001\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306e\u9069\u5207\u306a\u51e6\u7406\u306f\u6700\u3082\u57fa\u672c\u7684\u304b\u3064\u91cd\u8981\u306a\u5bfe\u7b56\u3067\u3059\u3002\u7279\u306bPHP\u3067\u306f\u3001\u578b\u5909\u63db\u306e\u51e6\u7406\u304c\u4e0d\u9069\u5207\u3060\u3068\u69d8\u3005\u306a\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u8106\u5f31\u6027\u306b\u3064\u306a\u304c\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>SQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306e\u9632\u6b62<\/strong><\/p>\n\n\n\n<p>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3068\u306e\u9023\u643a\u3067\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3092\u76f4\u63a5SQL\u30af\u30a8\u30ea\u306b\u542b\u3081\u308b\u3053\u3068\u306f\u5371\u967a\u3067\u3059\u3002\u7279\u306bID\u306a\u3069\u6574\u6570\u5024\u3068\u3057\u3066\u6271\u308f\u308c\u308b\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u9069\u5207\u306b\u5909\u63db\u3057\u306a\u3044\u3068\u3001SQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u653b\u6483\u306e\u6a19\u7684\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5371\u967a\u306a\u5b9f\u88c5 - SQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306e\u53ef\u80fd\u6027\u3042\u308a\n$user_id = $_GET['id']; \/\/ \u4f8b\uff1a\"1 OR 1=1\"\n$query = \"SELECT * FROM users WHERE id = $user_id\";\n\/\/ \u7d50\u679c\uff1a\u5168\u30e6\u30fc\u30b6\u30fc\u60c5\u5831\u304c\u6f0f\u6d29\u3059\u308b\u53ef\u80fd\u6027\n\n\/\/ \u5b89\u5168\u306a\u5b9f\u88c5 - intval()\u306b\u3088\u308b\u6574\u6570\u5909\u63db\n$user_id = intval($_GET['id']); \/\/ \"1 OR 1=1\" \u2192 1\n$query = \"SELECT * FROM users WHERE id = $user_id\";\n\/\/ \u7d50\u679c\uff1aID=1\u306e\u30e6\u30fc\u30b6\u30fc\u60c5\u5831\u306e\u307f\u304c\u53d6\u5f97\u3055\u308c\u308b\n<\/pre>\n\n\n\n<p><strong>\u6a29\u9650\u6607\u683c\u306e\u9632\u6b62<\/strong><\/p>\n\n\n\n<p>\u30e6\u30fc\u30b6\u30fc\u8a8d\u8a3c\u3084\u6a29\u9650\u30c1\u30a7\u30c3\u30af\u3067\u306f\u3001ID\u3084\u30ed\u30fc\u30eb\u306e\u5024\u304c\u9069\u5207\u306b\u578b\u5909\u63db\u3055\u308c\u3066\u3044\u306a\u3044\u3068\u3001\u6a29\u9650\u30c1\u30a7\u30c3\u30af\u3092\u30d0\u30a4\u30d1\u30b9\u3055\u308c\u308b\u5371\u967a\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5371\u967a\u306a\u5b9f\u88c5 - \u6a29\u9650\u30d0\u30a4\u30d1\u30b9\u306e\u53ef\u80fd\u6027\u3042\u308a\nif ($_GET['admin'] == 0) { \/\/ \"0admin\" \u3084\u7a7a\u6587\u5b57\u3082 0 \u3068\u8a55\u4fa1\u3055\u308c\u308b\u53ef\u80fd\u6027\n    \/\/ \u7ba1\u7406\u8005\u6a5f\u80fd\u306b\u30a2\u30af\u30bb\u30b9\u8a31\u53ef\n}\n\n\/\/ \u5b89\u5168\u306a\u5b9f\u88c5 - \u660e\u793a\u7684\u306a\u578b\u5909\u63db\u3068\u53b3\u5bc6\u6bd4\u8f03\n$is_admin = intval($_GET['admin']);\nif ($is_admin === 0) {\n    \/\/ \u7ba1\u7406\u8005\u6a5f\u80fd\u306b\u30a2\u30af\u30bb\u30b9\u8a31\u53ef\n}\n<\/pre>\n\n\n\n<p><strong>\u30d1\u30e9\u30e1\u30fc\u30bf\u6539\u3056\u3093\u5bfe\u7b56<\/strong><\/p>\n\n\n\n<p>\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u3084\u30ea\u30bd\u30fc\u30b9ID\u306a\u3069\u3001\u6570\u5024\u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u6539\u3056\u3093\u306b\u3088\u308b\u8106\u5f31\u6027\u3082\u8003\u616e\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5b89\u5168\u306a\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\n$page = intval($_GET['page']);\nif ($page &lt; 1) $page = 1; \/\/ \u8ca0\u306e\u5024\u3084\u6587\u5b57\u5217\u306e\u5bfe\u7b56\n$limit = 10;\n$offset = ($page - 1) * $limit;\n\n$query = \"SELECT * FROM products LIMIT $limit OFFSET $offset\";\n<\/pre>\n\n\n\n<p><strong>\u8ffd\u52a0\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u5bfe\u7b56<\/strong><\/p>\n\n\n\n<p><code>intval()<\/code>\u306f\u5f37\u529b\u306a\u30c4\u30fc\u30eb\u3067\u3059\u304c\u3001\u5358\u72ec\u3067\u306f\u5b8c\u5168\u306a\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3092\u4fdd\u8a3c\u3059\u308b\u3082\u306e\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u4ee5\u4e0b\u306e\u5bfe\u7b56\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5805\u7262\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u69cb\u7bc9\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7bc4\u56f2\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3<\/strong>: \u6574\u6570\u5024\u306e\u7bc4\u56f2\u304c\u59a5\u5f53\u304b\u3069\u3046\u304b\u3092\u691c\u8a3c\u3059\u308b<\/li>\n\n\n\n<li><strong>\u30d7\u30ea\u30da\u30a2\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8<\/strong>: \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u3067\u306f\u30d7\u30ea\u30da\u30a2\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u3092\u4f7f\u7528\u3059\u308b<\/li>\n\n\n\n<li><strong>CSRF\u5bfe\u7b56<\/strong>: \u91cd\u8981\u306a\u64cd\u4f5c\u3067\u306fCSRF\u30c8\u30fc\u30af\u30f3\u3092\u5b9f\u88c5\u3059\u308b<\/li>\n\n\n\n<li><strong>\u30a8\u30e9\u30fc\u51e6\u7406<\/strong>: \u4e0d\u6b63\u306a\u5165\u529b\u3092\u691c\u51fa\u3057\u305f\u5834\u5408\u306f\u9069\u5207\u306a\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u8868\u793a\u3059\u308b<\/li>\n<\/ol>\n\n\n\n<p>\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u306e\u89b3\u70b9\u304b\u3089\u306f\u3001\u300c\u4fe1\u983c\u305b\u305a\u3001\u691c\u8a3c\u3059\u308b\u300d\u306e\u539f\u5247\u306b\u5f93\u3044\u3001\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306f\u5e38\u306b\u6f5c\u5728\u7684\u306a\u8105\u5a01\u3068\u3057\u3066\u6271\u3044\u3001<code>intval()<\/code>\u306a\u3069\u306e\u9069\u5207\u306a\u578b\u5909\u63db\u3068\u691c\u8a3c\u3092\u884c\u3046\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-6\">intval()\u306e7\u3064\u306e\u5b9f\u8df5\u7684\u306a\u4f7f\u7528\u30b7\u30fc\u30f3<\/h2>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u4e00\u898b\u30b7\u30f3\u30d7\u30eb\u3067\u3059\u304c\u3001\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306f\u69d8\u3005\u306a\u72b6\u6cc1\u3067\u6d3b\u8e8d\u3057\u307e\u3059\u3002\u3053\u3053\u3067\u306f\u3001PHP\u958b\u767a\u8005\u304c\u65e5\u5e38\u7684\u306b\u906d\u9047\u3059\u308b7\u3064\u306e\u5b9f\u8df5\u7684\u306a\u4f7f\u7528\u30b7\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u7fd2\u5f97\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5805\u7262\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u304c\u53ef\u80fd\u306b\u306a\u308b\u3067\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-7\">\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u5024\u306e\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>Web\u30d5\u30a9\u30fc\u30e0\u304b\u3089\u9001\u4fe1\u3055\u308c\u308b\u30c7\u30fc\u30bf\u306f\u5e38\u306b\u6587\u5b57\u5217\u578b\u3067\u3059\u3002\u30e6\u30fc\u30b6\u30fc\u304c\u5165\u529b\u3057\u305f\u5546\u54c1\u6570\u91cf\u3084\u91d1\u984d\u306a\u3069\u306e\u6570\u5024\u30c7\u30fc\u30bf\u3092\u9069\u5207\u306b\u51e6\u7406\u3059\u308b\u306b\u306f\u3001\u78ba\u5b9f\u306a\u578b\u5909\u63db\u304c\u5fc5\u8981\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30d5\u30a9\u30fc\u30e0\u304b\u3089\u9001\u4fe1\u3055\u308c\u305f\u5546\u54c1\u6570\u91cf\u3092\u5b89\u5168\u306b\u51e6\u7406\u3059\u308b\u4f8b\n$quantity = isset($_POST['quantity']) ? intval($_POST['quantity']) : 0;\n\n\/\/ \u8ca0\u306e\u5024\u3084\u4e0d\u6b63\u5024\u3078\u306e\u5bfe\u5fdc\nif ($quantity &lt;= 0) {\n    $quantity = 1; \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u8a2d\u5b9a\n}\n\n\/\/ \u5728\u5eab\u6570\u3068\u306e\u6bd4\u8f03\n$max_stock = 100;\nif ($quantity &gt; $max_stock) {\n    $quantity = $max_stock; \/\/ \u5728\u5eab\u6570\u3092\u8d85\u3048\u306a\u3044\u3088\u3046\u5236\u9650\n}\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-8\">\u6587\u5b57\u5217\u5185\u306e\u6570\u5024\u3092\u62bd\u51fa\u3059\u308b\u969b\u306e\u6d3b\u7528\u6cd5<\/h3>\n\n\n\n<p>\u30c6\u30ad\u30b9\u30c8\u30c7\u30fc\u30bf\u304b\u3089\u6570\u5024\u90e8\u5206\u306e\u307f\u3092\u62bd\u51fa\u3057\u305f\u3044\u5834\u5408\u3001<code>intval()<\/code>\u306f\u975e\u5e38\u306b\u4fbf\u5229\u3067\u3059\u3002\u5546\u54c1\u8aac\u660e\u3084\u5546\u54c1\u30b3\u30fc\u30c9\u304b\u3089\u6570\u5b57\u3060\u3051\u3092\u53d6\u308a\u51fa\u3059\u969b\u306b\u6d3b\u7528\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u300c\u5546\u54c1\u756a\u53f7:ABC-12345\u300d\u304b\u3089\u756a\u53f7\u90e8\u5206\u306e\u307f\u3092\u62bd\u51fa\n$product_code = \"\u5546\u54c1\u756a\u53f7:ABC-12345\";\n$numeric_part = intval(preg_replace('\/[^0-9]\/', '', $product_code)); \/\/ 12345\n\n\/\/ \u4fa1\u683c\u8868\u8a18\u304b\u3089\u6570\u5024\u306e\u307f\u3092\u53d6\u5f97\n$price_text = \"\u00a55,800\uff08\u7a0e\u8fbc\uff09\";\n$price_value = intval(preg_replace('\/[^0-9]\/', '', $price_text)); \/\/ 5800\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-9\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5024\u306e\u578b\u4fdd\u8a3c\u306b\u5f79\u7acb\u3064\u30b1\u30fc\u30b9<\/h3>\n\n\n\n<p>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u306e\u7d50\u679c\u306f\u3001\u30ab\u30e9\u30e0\u306e\u578b\u306b\u95a2\u308f\u3089\u305a\u6587\u5b57\u5217\u3068\u3057\u3066\u6271\u308f\u308c\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u7279\u306b\u96c6\u8a08\u95a2\u6570\u3084\u6570\u5024\u8a08\u7b97\u3092\u884c\u3046\u969b\u306b\u306f\u3001\u78ba\u5b9f\u306b\u6574\u6570\u578b\u306b\u5909\u63db\u3059\u308b\u3053\u3068\u3067\u60f3\u5b9a\u5916\u306e\u52d5\u4f5c\u3092\u9632\u6b62\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5546\u54c1ID\u3092\u78ba\u5b9f\u306b\u6574\u6570\u578b\u306b\u5909\u63db\n$stmt = $pdo-&gt;prepare(\"SELECT id FROM products WHERE category = ?\");\n$stmt-&gt;execute(['electronics']);\n$product_ids = [];\n\nwhile ($row = $stmt-&gt;fetch(PDO::FETCH_ASSOC)) {\n    $product_ids[] = intval($row['id']); \/\/ \u78ba\u5b9f\u306b\u6574\u6570\u578b\u306e\u914d\u5217\u3092\u4f5c\u6210\n}\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-10\">\u7570\u306a\u308b\u57fa\u6570\u3067\u306e\u6570\u5024\u89e3\u91c8 \u2013 2\u9032\u6570\u30fb8\u9032\u6570\u30fb16\u9032\u6570\u5bfe\u5fdc<\/h3>\n\n\n\n<p><code>intval()<\/code>\u306e\u7b2c\u4e8c\u5f15\u6570\u3092\u4f7f\u7528\u3059\u308b\u3068\u3001\u7570\u306a\u308b\u57fa\u6570\uff082\u9032\u6570\u30018\u9032\u6570\u300116\u9032\u6570\u306a\u3069\uff09\u306e\u6587\u5b57\u5217\u309210\u9032\u6570\u6574\u6570\u306b\u5909\u63db\u3067\u304d\u307e\u3059\u3002\u3053\u308c\u306f\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u306e\u51e6\u7406\u3084\u30d3\u30c3\u30c8\u6f14\u7b97\u3067\u7279\u306b\u5f79\u7acb\u3061\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ HTML\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u3092RGB\u5024\u306b\u5909\u63db\n$color = \"#FF5733\";\n$r = intval(substr($color, 1, 2), 16); \/\/ 255\n$g = intval(substr($color, 3, 2), 16); \/\/ 87\n$b = intval(substr($color, 5, 2), 16); \/\/ 51\n\n\/\/ IP\u30a2\u30c9\u30ec\u30b9\u306e16\u9032\u6570\u8868\u8a18\u309210\u9032\u6570\u306b\u5909\u63db\n$ip_hex = \"C0A80101\"; \/\/ 192.168.1.1\u306e16\u9032\u6570\u8868\u8a18\n$ip_dec = intval($ip_hex, 16); \/\/ 3232235777\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u969b\u306e\u6ce8\u610f\u70b9<\/h3>\n\n\n\n<p>\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u5834\u5408\u3001<code>intval()<\/code>\u306f\u5c0f\u6570\u70b9\u4ee5\u4e0b\u3092\u5207\u308a\u6368\u3066\u307e\u3059\u3002\u3053\u306e\u6319\u52d5\u306f\u7279\u306b\u91d1\u984d\u8a08\u7b97\u3084\u5e73\u5747\u5024\u306e\u51e6\u7406\u3067\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5c0f\u6570\u70b9\u4ee5\u4e0b\u306e\u5207\u308a\u6368\u3066\necho intval(42.8);  \/\/ 42\necho intval(-42.8); \/\/ -42\n\n\/\/ \u901a\u8ca8\u8a08\u7b97\u3067\u306e\u6ce8\u610f\u70b9\uff08\u7aef\u6570\u5207\u308a\u6368\u3066\uff09\n$price = 1256.78;\n$price_without_tax = intval($price \/ 1.1); \/\/ 1142\uff08\u6b63\u78ba\u306b\u306f1142.52...\uff09\n\n\/\/ \u5207\u308a\u4e0a\u3052\u304c\u5fc5\u8981\u306a\u5834\u5408\u306fceil()\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\n$price_without_tax = intval(ceil($price \/ 1.1)); \/\/ 1143\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-12\">\u914d\u5217\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308bintval()\u306e\u6319\u52d5\u3068\u5bfe\u51e6\u6cd5<\/h3>\n\n\n\n<p><code>intval()<\/code>\u306f\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3057\u3066\u3082\u4f7f\u7528\u3067\u304d\u307e\u3059\u304c\u3001\u305d\u306e\u6319\u52d5\u306fPHP\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u7570\u306a\u308a\u307e\u3059\u3002\u4e00\u822c\u7684\u306b\u306f\u3001\u305d\u308c\u3089\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u3053\u3068\u306f\u610f\u56f3\u3057\u305f\u52d5\u4f5c\u3067\u306f\u306a\u3044\u305f\u3081\u3001\u9069\u5207\u306a\u4ee3\u66ff\u624b\u6bb5\u3092\u4f7f\u7528\u3059\u3079\u304d\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PHP 7.3\u4ee5\u524d\u3067\u306f1\u3092\u8fd4\u3057\u3001PHP 7.4\u4ee5\u964d\u306f\u8b66\u544a\u304c\u767a\u751f\u3057\u30660\u3092\u8fd4\u3059\n$result = intval([1, 2, 3]);\n\n\/\/ \u4ee3\u308f\u308a\u306b\u914d\u5217\u306e\u8981\u7d20\u306b\u5bfe\u3057\u3066\u9069\u7528\u3059\u308b\n$array = [\"1\", \"2\", \"3abc\", \"four\"];\n$integers = array_map('intval', $array); \/\/ [1, 2, 3, 0]\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-13\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6570\u5024\u51e6\u7406\u306b\u304a\u3051\u308b\u5b9f\u88c5\u4f8b<\/h3>\n\n\n\n<p>\u5916\u90e8API\u3068\u306e\u9023\u643a\u3067\u306f\u3001JSON\u30c7\u30fc\u30bf\u306a\u3069\u306b\u542b\u307e\u308c\u308b\u6570\u5024\u304c\u6587\u5b57\u5217\u3068\u3057\u3066\u8868\u73fe\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u304c\u3088\u304f\u3042\u308a\u307e\u3059\u3002\u3053\u308c\u3089\u3092\u9069\u5207\u306b\u51e6\u7406\u3059\u308b\u305f\u3081\u306b<code>intval()<\/code>\u304c\u6d3b\u7528\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ JSON\u30ec\u30b9\u30dd\u30f3\u30b9\u3092\u51e6\u7406\u3059\u308b\u4f8b\n$json_response = '{\"id\":\"1234\",\"quantity\":\"5\",\"price\":\"1299\"}';\n$data = json_decode($json_response, true);\n\n\/\/ \u6570\u5024\u3068\u3057\u3066\u6271\u3044\u305f\u3044\u30d5\u30a3\u30fc\u30eb\u30c9\u3092\u5909\u63db\n$order = [\n    'id' =&gt; intval($data['id']),\n    'quantity' =&gt; intval($data['quantity']),\n    'price' =&gt; intval($data['price']),\n    'total' =&gt; intval($data['quantity']) * intval($data['price'])\n];\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u5024\u306e\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>Web\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u306b\u304a\u3044\u3066\u3001\u30d5\u30a9\u30fc\u30e0\u304b\u3089\u306e\u5165\u529b\u5024\u306f\u6700\u3082\u4e00\u822c\u7684\u306a\u30c7\u30fc\u30bf\u30bd\u30fc\u30b9\u306e\u4e00\u3064\u3067\u3059\u3002\u3057\u304b\u3057\u6ce8\u610f\u3059\u3079\u304d\u70b9\u3068\u3057\u3066\u3001HTML form\u304b\u3089\u9001\u4fe1\u3055\u308c\u308b\u3059\u3079\u3066\u306e\u5024\u306f<strong>\u6587\u5b57\u5217\u578b<\/strong>\u3068\u3057\u3066\u53d7\u3051\u53d6\u3089\u308c\u307e\u3059\u3002\u3053\u308c\u306f<code>&lt;input type=\"number\"&gt;<\/code>\u306e\u3088\u3046\u306a\u6570\u5024\u5165\u529b\u30d5\u30a3\u30fc\u30eb\u30c9\u3067\u3042\u3063\u3066\u3082\u540c\u69d8\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u30e6\u30fc\u30b6\u30fc\u304b\u3089\u53d7\u3051\u53d6\u3063\u305f\u300c\u6570\u91cf\u300d\u3084\u300c\u91d1\u984d\u300d\u306a\u3069\u306e\u5024\u3092\u8a08\u7b97\u306b\u4f7f\u7528\u3059\u308b\u5834\u5408\u3001\u78ba\u5b9f\u306b\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u306e\u3088\u3046\u306a\u30b7\u30ca\u30ea\u30aa\u3067<code>intval()<\/code>\u95a2\u6570\u304c\u975e\u5e38\u306b\u5f79\u7acb\u3061\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u57fa\u672c\u7684\u306a\u4f7f\u7528\u30d1\u30bf\u30fc\u30f3\n$quantity = intval($_POST['quantity']);\n\n\/\/ \u3088\u308a\u5b8c\u5168\u306a\u5b9f\u88c5\u4f8b\nif (isset($_POST['quantity'])) {\n    $quantity = intval($_POST['quantity']);\n    \/\/ \u4ee5\u964d\u306e\u51e6\u7406...\n}\n<\/pre>\n\n\n\n<p>\u305f\u3060\u3057\u3001\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u3084\u7a7a\u306e\u5834\u5408\u306e\u5bfe\u5fdc\u3082\u8003\u616e\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002PHP 7\u4ee5\u964d\u3067\u306f\u3001null\u5408\u4f53\u6f14\u7b97\u5b50\uff08??\uff09\u3092\u4f7f\u3063\u3066\u7c21\u6f54\u306b\u8a18\u8ff0\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PHP 7\u4ee5\u964d\u306e\u63a8\u5968\u30d1\u30bf\u30fc\u30f3\n$quantity = intval($_POST['quantity'] ?? 0); \/\/ \u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306f0\u3092\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u306b\n\n\/\/ \u6700\u5c0f\u5024\u3092\u4fdd\u8a3c\uff08\u8ca0\u306e\u5024\u30840\u304c\u8a31\u5bb9\u3055\u308c\u306a\u3044\u5834\u5408\uff09\n$quantity = max(1, intval($_POST['quantity'] ?? 0));\n<\/pre>\n\n\n\n<p>\u5b9f\u969b\u306e\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306f\u3001\u5024\u306e\u7bc4\u56f2\u30c1\u30a7\u30c3\u30af\u3082\u91cd\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u7bc4\u56f2\u5185\u306b\u53ce\u3081\u308b\uff08\u4f8b: 1\u301c100\u306e\u7bc4\u56f2\uff09\n$quantity = intval($_POST['quantity'] ?? 0);\nif ($quantity &lt; 1) {\n    $quantity = 1; \/\/ \u6700\u5c0f\u5024\u3092\u9069\u7528\n} elseif ($quantity &gt; 100) {\n    $quantity = 100; \/\/ \u6700\u5927\u5024\u3092\u9069\u7528\n}\n\n\/\/ \u3088\u308a\u7c21\u6f54\u306a\u66f8\u304d\u65b9\n$quantity = min(max(1, intval($_POST['quantity'] ?? 0)), 100);\n<\/pre>\n\n\n\n<p>\u3088\u308a\u5805\u7262\u306a\u5b9f\u88c5\u3067\u306f\u3001\u578b\u5909\u63db\u306e\u524d\u306b\u5165\u529b\u691c\u8a3c\u3092\u884c\u3046\u3053\u3068\u3082\u91cd\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$errors = [];\n$quantity = 0;\n\n\/\/ \u5165\u529b\u691c\u8a3c\u306e\u4f8b\nif (!isset($_POST['quantity']) || $_POST['quantity'] === '') {\n    $errors[] = '\u6570\u91cf\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\u3002';\n} elseif (!is_numeric($_POST['quantity'])) {\n    $errors[] = '\u6570\u91cf\u306f\u6570\u5024\u3067\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\u3002';\n} else {\n    $quantity = intval($_POST['quantity']);\n    if ($quantity &lt;= 0) {\n        $errors[] = '\u6570\u91cf\u306f1\u4ee5\u4e0a\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\u3002';\n    }\n}\n<\/pre>\n\n\n\n<p>PHP\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u6a5f\u80fd\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u6574\u7406\u3055\u308c\u305f\u5b9f\u88c5\u304c\u53ef\u80fd\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ Laravel\u306e\u4f8b\n$validated = $request-&gt;validate([\n    'quantity' =&gt; 'required|numeric|min:1|max:100',\n]);\n$quantity = intval($validated['quantity']);\n<\/pre>\n\n\n\n<p>\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u5024\u306e\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u306f\u3001\u5358\u306a\u308b\u578b\u5909\u63db\u3060\u3051\u3067\u306a\u304f\u3001\u9069\u5207\u306a\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5b89\u5168\u3067\u4fe1\u983c\u6027\u306e\u9ad8\u3044\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u306b\u3064\u306a\u304c\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-15\">\u6587\u5b57\u5217\u5185\u306e\u6570\u5024\u3092\u62bd\u51fa\u3059\u308b\u969b\u306e\u6d3b\u7528\u6cd5<\/h3>\n\n\n\n<p>\u5b9f\u969b\u306eWeb\u958b\u767a\u3067\u306f\u3001\u30c6\u30ad\u30b9\u30c8\u30c7\u30fc\u30bf\u304b\u3089\u6570\u5024\u90e8\u5206\u306e\u307f\u3092\u62bd\u51fa\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u30b1\u30fc\u30b9\u304c\u983b\u7e41\u306b\u767a\u751f\u3057\u307e\u3059\u3002\u4f8b\u3048\u3070\u3001\u5546\u54c1\u30b3\u30fc\u30c9\u304b\u3089\u6570\u5024ID\u90e8\u5206\u3060\u3051\u3092\u53d6\u308a\u51fa\u3057\u305f\u308a\u3001\u4fa1\u683c\u8868\u8a18\u304b\u3089\u91d1\u984d\u306e\u307f\u3092\u62bd\u51fa\u3057\u305f\u308a\u3059\u308b\u5834\u9762\u3067\u3059\u3002<code>intval()<\/code>\u95a2\u6570\u306f\u3053\u306e\u3088\u3046\u306a\u72b6\u6cc1\u3067\u975e\u5e38\u306b\u5f79\u7acb\u3061\u307e\u3059\u3002<\/p>\n\n\n\n<p><code>intval()<\/code>\u306f\u6587\u5b57\u5217\u3092\u89e3\u6790\u3059\u308b\u969b\u3001\u5148\u982d\u304b\u3089\u6570\u5024\u3068\u3057\u3066\u8a8d\u8b58\u3067\u304d\u308b\u90e8\u5206\u3060\u3051\u3092\u53d6\u308a\u51fa\u3057\u307e\u3059\u3002\u3053\u306e\u7279\u6027\u3092\u5229\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u30b7\u30f3\u30d7\u30eb\u306a\u30b1\u30fc\u30b9\u3067\u306f\u5bb9\u6613\u306b\u6570\u5024\u62bd\u51fa\u304c\u53ef\u80fd\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u57fa\u672c\u7684\u306a\u6570\u5024\u62bd\u51fa\necho intval(\"42abc\");       \/\/ \u7d50\u679c: 42\necho intval(\"\u4fa1\u683c: 100\u5186\"); \/\/ \u7d50\u679c: 0\uff08\u5148\u982d\u304c\u6570\u5b57\u3067\u306a\u3044\u305f\u3081\uff09\n<\/pre>\n\n\n\n<p>\u305f\u3060\u3057\u3001\u591a\u304f\u306e\u5b9f\u8df5\u7684\u306a\u72b6\u6cc1\u3067\u306f\u3001\u6587\u5b57\u5217\u306e\u5148\u982d\u304c\u6570\u5b57\u3067\u306a\u3044\u5834\u5408\u3084\u3001\u30ab\u30f3\u30de\u533a\u5207\u308a\u306e\u6570\u5024\u306a\u3069\u3001\u3088\u308a\u8907\u96d1\u306a\u30d1\u30bf\u30fc\u30f3\u3092\u51e6\u7406\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u306e\u3088\u3046\u306a\u5834\u5408\u306f\u3001\u6b63\u898f\u8868\u73fe\u3068<code>intval()<\/code>\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3068\u52b9\u679c\u7684\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6587\u5b57\u5217\u304b\u3089\u6570\u5b57\u4ee5\u5916\u306e\u6587\u5b57\u3092\u9664\u53bb\u3057\u3066\u304b\u3089\u5909\u63db\n$product_code = \"ABC-12345\";\n$numeric_part = intval(preg_replace('\/[^0-9]\/', '', $product_code));\necho $numeric_part; \/\/ \u7d50\u679c: 12345\n\n\/\/ \u30ab\u30f3\u30de\u533a\u5207\u308a\u306e\u4fa1\u683c\u304b\u3089\u6570\u5024\u3092\u62bd\u51fa\n$price_text = \"\u00a51,234,567\";\n$price_value = intval(preg_replace('\/[^0-9]\/', '', $price_text));\necho $price_value; \/\/ \u7d50\u679c: 1234567\n<\/pre>\n\n\n\n<p>\u5b9f\u52d9\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30b7\u30ca\u30ea\u30aa\u3067\u7279\u306b\u6d3b\u7528\u3067\u304d\u307e\u3059:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5546\u54c1\u8b58\u5225\u5b50\u304b\u3089\u306e\u6570\u5024\u62bd\u51fa<\/strong> <code>\/\/ \u5546\u54c1\u30b3\u30fc\u30c9\u304b\u3089\u6570\u5024ID\u90e8\u5206\u3092\u62bd\u51fa $sku = \"SHIRT-XL-12345\"; $product_id = intval(preg_replace('\/[^0-9]\/', '', $sku)); \/\/ 12345<\/code><\/li>\n\n\n\n<li><strong>\u5358\u4f4d\u4ed8\u304d\u6570\u5024\u306e\u51e6\u7406<\/strong> <code>\/\/ \u5358\u4f4d\u4ed8\u304d\u6570\u5024\u304b\u3089\u6570\u5024\u90e8\u5206\u306e\u307f\u3092\u53d6\u5f97 $weight = \"5kg\"; $weight_value = intval($weight); \/\/ 5\uff08\u5148\u982d\u304c\u6570\u5b57\u306e\u305f\u3081\u5358\u7d14\u306b\u5909\u63db\u53ef\u80fd\uff09 $height = \"\u8eab\u9577170cm\"; $height_value = intval(preg_replace('\/[^0-9]\/', '', $height)); \/\/ 170<\/code><\/li>\n\n\n\n<li><strong>\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306e\u30af\u30ea\u30fc\u30cb\u30f3\u30b0<\/strong> <code>\/\/ \u30e6\u30fc\u30b6\u30fc\u304c\u5165\u529b\u3057\u305f\u96fb\u8a71\u756a\u53f7\u304b\u3089\u6570\u5b57\u306e\u307f\u3092\u62bd\u51fa $phone_input = \"090-1234-5678\"; $phone_clean = intval(preg_replace('\/[^0-9]\/', '', $phone_input)); \/\/ 9012345678<\/code><\/li>\n<\/ol>\n\n\n\n<p>\u7279\u306b\u3001\u30c7\u30fc\u30bf\u306e\u30a4\u30f3\u30dd\u30fc\u30c8\u3084\u5916\u90e8\u30b7\u30b9\u30c6\u30e0\u3068\u306e\u9023\u643a\u3067\u306f\u3001\u3053\u306e\u624b\u6cd5\u304c\u975e\u5e38\u306b\u5f79\u7acb\u3061\u307e\u3059\u3002\u4f8b\u3048\u3070\u3001CSV\u30d5\u30a1\u30a4\u30eb\u304b\u3089\u30a4\u30f3\u30dd\u30fc\u30c8\u3057\u305f\u30c7\u30fc\u30bf\u306e\u4e2d\u306b\u300c\u5358\u4f4d\u4ed8\u304d\u306e\u6570\u5024\u300d\u3084\u300c\u7279\u6b8a\u306a\u5f62\u5f0f\u306e\u6570\u5024\u300d\u304c\u542b\u307e\u308c\u3066\u3044\u308b\u5834\u5408\u3067\u3082\u3001\u7c21\u5358\u306b\u6570\u5024\u90e8\u5206\u3060\u3051\u3092\u62bd\u51fa\u3057\u3066\u51e6\u7406\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u305f\u3060\u3057\u3001<code>intval()<\/code>\u306e\u5236\u9650\u3068\u3057\u3066\u3001PHP\u306e\u6574\u6570\u306e\u6700\u5927\u5024\uff08\u901a\u5e38\u306f32\u30d3\u30c3\u30c8\u30b7\u30b9\u30c6\u30e0\u3067\u7d0421\u5104\u300164\u30d3\u30c3\u30c8\u30b7\u30b9\u30c6\u30e0\u3067\u306f\u7d04922\u4eac\uff09\u3092\u8d85\u3048\u308b\u6570\u5024\u3092\u6271\u3046\u5834\u5408\u306f\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002\u3053\u306e\u3088\u3046\u306a\u5834\u5408\u306f\u3001<code>bcmath<\/code>\u62e1\u5f35\u306a\u3069\u306e\u5927\u304d\u306a\u6570\u5024\u3092\u6271\u3046\u305f\u3081\u306e\u7279\u5225\u306a\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3092\u691c\u8a0e\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-16\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5024\u306e\u578b\u4fdd\u8a3c\u306b\u5f79\u7acb\u3064\u30b1\u30fc\u30b9<\/h3>\n\n\n\n<p>PHP\u3067\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u3092\u884c\u3046\u958b\u767a\u8005\u306a\u3089\u3001\u610f\u5916\u306a\u4e8b\u5b9f\u306b\u6c17\u3065\u3044\u3066\u3044\u308b\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002\u305d\u308c\u306f\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u5185\u3067\u6574\u6570\u578b\uff08INT\uff09\u3068\u3057\u3066\u5b9a\u7fa9\u3055\u308c\u3066\u3044\u308b\u30ab\u30e9\u30e0\u306e\u5024\u3067\u3055\u3048\u3001PHP\u3067\u53d6\u5f97\u3059\u308b\u3068<strong>\u591a\u304f\u306e\u5834\u5408\u6587\u5b57\u5217\u578b\u3068\u3057\u3066<\/strong>\u8fd4\u3055\u308c\u308b\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u3053\u308c\u306fPDO\u3084mysqli\u3068\u3044\u3063\u305f\u4e00\u822c\u7684\u306a\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u63a5\u7d9a\u30e9\u30a4\u30d6\u30e9\u30ea\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u52d5\u4f5c\u3067\u3042\u308a\u3001\u3057\u3070\u3057\u3070\u6df7\u4e71\u3084\u5fae\u5999\u306a\u30d0\u30b0\u306e\u539f\u56e0\u3068\u306a\u308a\u307e\u3059\u3002\u4ee5\u4e0b\u306f\u3001\u3053\u306e\u554f\u984c\u306e\u5177\u4f53\u4f8b\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PDO\u3092\u4f7f\u7528\u3057\u305f\u4f8b\n$stmt = $pdo-&gt;query(\"SELECT id, quantity FROM orders WHERE id = 1\");\n$order = $stmt-&gt;fetch(PDO::FETCH_ASSOC);\n\nvar_dump($order['id']);      \/\/ \u7d50\u679c: string(1) \"1\"\nvar_dump($order['quantity']); \/\/ \u7d50\u679c: string(2) \"10\"\n\n\/\/ \u6587\u5b57\u5217\u540c\u58eb\u306e\u6bd4\u8f03\n$order_id = $order['id'];\nif ($order_id == 1) {    \/\/ \u578b\u5909\u63db\u304c\u767a\u751f\u3059\u308b\u305f\u3081\u52d5\u4f5c\u3059\u308b\n    \/\/ \u51e6\u7406...\n}\n<\/pre>\n\n\n\n<p>PDO\u3067\u306f<code>PDO::ATTR_EMULATE_PREPARES<\/code>\u3068<code>PDO::ATTR_STRINGIFY_FETCHES<\/code>\u306e\u8a2d\u5b9a\u3092\u5909\u66f4\u3059\u308b\u3053\u3068\u3067\u3001\u3053\u306e\u6319\u52d5\u3092\u90e8\u5206\u7684\u306b\u5236\u5fa1\u3067\u304d\u307e\u3059\u304c\u3001\u74b0\u5883\u4f9d\u5b58\u3084\u30c9\u30e9\u30a4\u30d0\u4f9d\u5b58\u306e\u554f\u984c\u304c\u3042\u308a\u3001\u5b8c\u5168\u306a\u89e3\u6c7a\u7b56\u3068\u306f\u306a\u308a\u307e\u305b\u3093\u3002<\/p>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306a\u72b6\u6cc1\u3067<code>intval()<\/code>\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u3068\u3001\u4ee5\u4e0b\u306e\u30e1\u30ea\u30c3\u30c8\u304c\u5f97\u3089\u308c\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u578b\u306e\u4e00\u8cab\u6027\u3092\u78ba\u4fdd\u3067\u304d\u308b<\/strong>\uff1a\u30b3\u30fc\u30c9\u5168\u4f53\u3067\u5909\u6570\u306e\u578b\u306b\u95a2\u3059\u308b\u4e88\u6e2c\u53ef\u80fd\u6027\u304c\u9ad8\u307e\u308a\u307e\u3059<\/li>\n\n\n\n<li><strong>\u610f\u56f3\u3092\u660e\u793a\u3067\u304d\u308b<\/strong>\uff1a\u3053\u306e\u5909\u6570\u306f\u6574\u6570\u3068\u3057\u3066\u6271\u3046\u3079\u304d\u3068\u3044\u3046\u610f\u56f3\u304c\u660e\u78ba\u306b\u306a\u308a\u307e\u3059<\/li>\n\n\n\n<li><strong>\u8a08\u7b97\u306e\u5b89\u5168\u6027\u304c\u5411\u4e0a\u3059\u308b<\/strong>\uff1a\u6587\u5b57\u5217\u304b\u3089\u6570\u5024\u3078\u306e\u81ea\u52d5\u5909\u63db\u306b\u983c\u3089\u306a\u3044\u3001\u78ba\u5b9f\u306a\u8a08\u7b97\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059<\/li>\n<\/ol>\n\n\n\n<p>\u5b9f\u969b\u306e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u5834\u9762\u3067<code>intval()<\/code>\u306b\u3088\u308b\u578b\u5909\u63db\u304c\u7279\u306b\u5f79\u7acb\u3061\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7d50\u679c\u306e\u6574\u6570\u578b\u4fdd\u8a3c\n$stmt = $pdo-&gt;query(\"SELECT id, category_id, price FROM products\");\n$products = [];\n\nwhile ($row = $stmt-&gt;fetch(PDO::FETCH_ASSOC)) {\n    $products[] = [\n        'id' =&gt; intval($row['id']),\n        'category_id' =&gt; intval($row['category_id']),\n        'price' =&gt; intval($row['price']),\n        'name' =&gt; $row['name'] \/\/ \u6587\u5b57\u5217\u306f\u305d\u306e\u307e\u307e\n    ];\n}\n<\/pre>\n\n\n\n<p>\u7279\u306b\u96c6\u8a08\u51e6\u7406\u3084\u8907\u6570\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u6271\u3046\u5834\u5408\u3001\u578b\u4fdd\u8a3c\u306e\u91cd\u8981\u6027\u306f\u5897\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30ab\u30c6\u30b4\u30ea\u3054\u3068\u306e\u5546\u54c1\u6570\u96c6\u8a08\n$stmt = $pdo-&gt;query(\"SELECT category_id, COUNT(*) as product_count FROM products GROUP BY category_id\");\n$categories = [];\n\nwhile ($row = $stmt-&gt;fetch(PDO::FETCH_ASSOC)) {\n    \/\/ \u914d\u5217\u306e\u30ad\u30fc\u3068\u3057\u3066\u4f7f\u7528\u3059\u308b\u305f\u3081\u3001\u78ba\u5b9f\u306b\u6574\u6570\u5909\u63db\n    $category_id = intval($row['category_id']);\n    $categories[$category_id] = intval($row['product_count']);\n}\n<\/pre>\n\n\n\n<p>\u5b9f\u52d9\u7684\u306a\u30a2\u30d7\u30ed\u30fc\u30c1\u3068\u3057\u3066\u3001\u30c7\u30fc\u30bf\u30e2\u30c7\u30eb\u3084\u30ea\u30dd\u30b8\u30c8\u30ea\u30af\u30e9\u30b9\u5185\u3067\u4e00\u8cab\u3057\u305f\u578b\u5909\u63db\u3092\u884c\u3046\u30d1\u30bf\u30fc\u30f3\u3082\u52b9\u679c\u7684\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class Product {\n    public int $id;\n    public int $category_id;\n    public int $price;\n    public string $name;\n\n    public function __construct(array $data) {\n        $this-&gt;id = intval($data['id']);\n        $this-&gt;category_id = intval($data['category_id']);\n        $this-&gt;price = intval($data['price']);\n        $this-&gt;name = $data['name'];\n    }\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306b\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u30c7\u30fc\u30bf\u306b\u5bfe\u3057\u3066<code>intval()<\/code>\u3092\u9069\u5207\u306b\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5805\u7262\u3067\u4e88\u6e2c\u53ef\u80fd\u306a\u30b3\u30fc\u30c9\u3092\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-17\">\u7570\u306a\u308b\u57fa\u6570\u3067\u306e\u6570\u5024\u89e3\u91c8 \u2013 2\u9032\u6570\u30fb8\u9032\u6570\u30fb16\u9032\u6570\u5bfe\u5fdc<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306e\u96a0\u308c\u305f\u5f37\u529b\u306a\u6a5f\u80fd\u3068\u3057\u3066\u3001\u7b2c2\u5f15\u6570\u306b\u57fa\u6570\uff08\u9032\u6570\uff09\u3092\u6307\u5b9a\u3067\u304d\u308b\u70b9\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u306e\u6a5f\u80fd\u3092\u6d3b\u7528\u3059\u308b\u3068\u30012\u9032\u6570\u30018\u9032\u6570\u300116\u9032\u6570\u306a\u3069\u3001\u3055\u307e\u3056\u307e\u306a\u8a18\u6570\u6cd5\u3067\u8868\u3055\u308c\u305f\u6587\u5b57\u5217\u309210\u9032\u6570\u306e\u6574\u6570\u306b\u5909\u63db\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u57fa\u672c\u7684\u306a\u69cb\u6587\u306f\u6b21\u306e\u3068\u304a\u308a\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">intval(string $var, int $base = 10)\n<\/pre>\n\n\n\n<p>\u7b2c2\u5f15\u6570\u306b\u306f2\u301c36\u306e\u6574\u6570\u3092\u6307\u5b9a\u3067\u304d\u3001\u305d\u308c\u305e\u308c\u306e\u6570\u5024\u30b7\u30b9\u30c6\u30e0\u3067\u306e\u89e3\u91c8\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059\u3002\u4ee3\u8868\u7684\u306a\u57fa\u6570\u3067\u306e\u5909\u63db\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ 2\u9032\u6570\uff08\u30d0\u30a4\u30ca\u30ea\uff09\necho intval(\"1010\", 2);     \/\/ \u7d50\u679c: 10\necho intval(\"11111111\", 2); \/\/ \u7d50\u679c: 255\n\n\/\/ 8\u9032\u6570\uff08\u30aa\u30af\u30bf\u30eb\uff09\necho intval(\"12\", 8);       \/\/ \u7d50\u679c: 10\necho intval(\"377\", 8);      \/\/ \u7d50\u679c: 255\n\n\/\/ 16\u9032\u6570\uff08\u30d8\u30ad\u30b5\u30c7\u30b7\u30de\u30eb\uff09\necho intval(\"A\", 16);       \/\/ \u7d50\u679c: 10\necho intval(\"FF\", 16);      \/\/ \u7d50\u679c: 255\necho intval(\"ff\", 16);      \/\/ \u7d50\u679c: 255\uff08\u5927\u6587\u5b57\u5c0f\u6587\u5b57\u306f\u533a\u5225\u3055\u308c\u306a\u3044\uff09\n<\/pre>\n\n\n\n<p>\u3053\u306e\u6a5f\u80fd\u306f\u3001\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30b7\u30ca\u30ea\u30aa\u3067\u975e\u5e38\u306b\u5f79\u7acb\u3061\u307e\u3059\uff1a<\/p>\n\n\n\n<p><strong>1. HTML\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u306e\u51e6\u7406<\/strong><\/p>\n\n\n\n<p>Web\u30c7\u30b6\u30a4\u30f3\u3084\u30b0\u30e9\u30d5\u30a3\u30c3\u30af\u51e6\u7406\u3067\u306f\u3001\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u309216\u9032\u6570\u8868\u8a18\u304b\u308910\u9032\u6570\u306eRGB\u5024\u306b\u5909\u63db\u3059\u308b\u5834\u9762\u304c\u591a\u3005\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ #RRGGBB \u5f62\u5f0f\u306e\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u3092RGB\u5024\u306b\u5909\u63db\n$color = \"#FF5733\";\n$r = intval(substr($color, 1, 2), 16); \/\/ 255\n$g = intval(substr($color, 3, 2), 16); \/\/ 87\n$b = intval(substr($color, 5, 2), 16); \/\/ 51\n\n\/\/ RGB\u5024\u3092\u4f7f\u3063\u305f\u8a08\u7b97\uff08\u4f8b\uff1a\u660e\u308b\u3055\u306e\u8a08\u7b97\uff09\n$brightness = (($r * 299) + ($g * 587) + ($b * 114)) \/ 1000;\n<\/pre>\n\n\n\n<p><strong>2. \u30d3\u30c3\u30c8\u30d5\u30e9\u30b0\u3068\u6a29\u9650\u7ba1\u7406<\/strong><\/p>\n\n\n\n<p>\u30d3\u30c3\u30c8\u64cd\u4f5c\u306b\u3088\u308b\u30d5\u30e9\u30b0\u7ba1\u7406\u3084\u6a29\u9650\u8a2d\u5b9a\u3067\u306f\u30012\u9032\u6570\u8868\u8a18\u304b\u3089\u306e\u5909\u63db\u304c\u4fbf\u5229\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30e6\u30fc\u30b6\u30fc\u6a29\u9650\u30922\u9032\u6570\u8868\u8a18\u3067\u5b9a\u7fa9\uff08\u8aad\u307f\u8fbc\u307f=4, \u66f8\u304d\u8fbc\u307f=2, \u5b9f\u884c=1\uff09\n$permission_string = \"101\"; \/\/ \u8aad\u307f\u8fbc\u307f\u6a29\u9650\u3068\u5b9f\u884c\u6a29\u9650\u3042\u308a\n$permissions = intval($permission_string, 2); \/\/ 5\n\n\/\/ \u6a29\u9650\u30c1\u30a7\u30c3\u30af\nif ($permissions &amp; 4) {\n    echo \"\u8aad\u307f\u8fbc\u307f\u6a29\u9650\u304c\u3042\u308a\u307e\u3059\";\n}\n<\/pre>\n\n\n\n<p><strong>3. \u7279\u6b8a\u306a\u6570\u5024\u5f62\u5f0f\u306e\u51e6\u7406<\/strong><\/p>\n\n\n\n<p>\u69d8\u3005\u306a\u30b7\u30b9\u30c6\u30e0\u3084\u30d7\u30ed\u30c8\u30b3\u30eb\u3067\u306f\u7279\u6b8a\u306a\u6570\u5024\u8868\u8a18\u304c\u4f7f\u308f\u308c\u308b\u3053\u3068\u304c\u3042\u308a\u3001\u3053\u308c\u3089\u306e\u5909\u63db\u306b\u5f79\u7acb\u3061\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ MAC\u30a2\u30c9\u30ec\u30b9\u306e\u51e6\u7406\n$mac_part = \"1A\";\n$decimal_value = intval($mac_part, 16); \/\/ 26\n\n\/\/ IP\u30a2\u30c9\u30ec\u30b9\u306e16\u9032\u6570\u8868\u8a18\u3092\u901a\u5e38\u306e\u5f62\u5f0f\u306b\u5909\u63db\n$ip_hex = \"C0A80101\"; \/\/ 192.168.1.1 \u306e16\u9032\u6570\u8868\u73fe\n$ip_dec = intval($ip_hex, 16); \/\/ 3232235777\n<\/pre>\n\n\n\n<p><strong>\u6ce8\u610f\u70b9<\/strong><\/p>\n\n\n\n<p>\u57fa\u6570\u6307\u5b9a\u3067<code>intval()<\/code>\u3092\u4f7f\u7528\u3059\u308b\u969b\u306b\u306f\u3001\u3044\u304f\u3064\u304b\u306e\u91cd\u8981\u306a\u70b9\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u57fa\u6570\u6307\u5b9a\u306f<strong>\u6587\u5b57\u5217\u304b\u3089\u306e\u5909\u63db\u6642\u306b\u306e\u307f\u6709\u52b9<\/strong>\u3067\u3059\u3002<\/li>\n\n\n\n<li>\u6307\u5b9a\u3057\u305f\u57fa\u6570\u306b\u5bfe\u5fdc\u3057\u306a\u3044\u6587\u5b57\u304c\u542b\u307e\u308c\u308b\u5834\u5408\u3001\u305d\u306e\u6587\u5b57\u307e\u3067\u306e\u90e8\u5206\u306e\u307f\u304c\u5909\u63db\u3055\u308c\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u5927\u6587\u5b57\u3068\u5c0f\u6587\u5b57\u306f\u533a\u5225\u3055\u308c\u307e\u305b\u3093\uff08\u4f8b\uff1a16\u9032\u6570\u306e\u201dFF\u201d\u3068\u201dff\u201d\u306f\u540c\u3058\u5024\uff09\u3002<\/li>\n\n\n\n<li>\u57fa\u6570\u304c2\u301c36\u306e\u7bc4\u56f2\u5916\u306e\u5834\u5408\u3001\u81ea\u52d5\u7684\u306b10\uff0810\u9032\u6570\uff09\u3068\u3057\u3066\u6271\u308f\u308c\u307e\u3059\u3002<\/li>\n<\/ol>\n\n\n\n<p>\u7279\u306b16\u9032\u6570\u5909\u63db\u306f\u983b\u7e41\u306b\u4f7f\u7528\u3055\u308c\u308b\u305f\u3081\u3001\u5c02\u7528\u306e<code>hexdec()<\/code>\u95a2\u6570\u3082\u3042\u308a\u307e\u3059\u304c\u3001\u57fa\u6570\u3092\u53ef\u5909\u306b\u3057\u305f\u3044\u5834\u5408\u3084\u8907\u6570\u306e\u57fa\u6570\u3092\u6271\u3046\u5834\u5408\u306f<code>intval()<\/code>\u306e\u7b2c2\u5f15\u6570\u3092\u6d3b\u7528\u3059\u308b\u3068\u4fbf\u5229\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-18\">\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u969b\u306e\u6ce8\u610f\u70b9<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u3092\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u306b\u9069\u7528\u3059\u308b\u3068\u3001\u5c0f\u6570\u70b9\u4ee5\u4e0b\u304c<strong>\u5e38\u306b\u5207\u308a\u6368\u3066<\/strong>\u3089\u308c\u307e\u3059\u3002\u3053\u306e\u52d5\u4f5c\u306f\u5358\u7d14\u660e\u5feb\u3067\u3059\u304c\u3001\u7279\u306b\u8ca1\u52d9\u8a08\u7b97\u3084\u7cbe\u5bc6\u306a\u6570\u5024\u51e6\u7406\u304c\u5fc5\u8981\u306a\u5834\u9762\u3067\u306f\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u57fa\u672c\u7684\u306a\u6319\u52d5\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">echo intval(42.0);    \/\/ \u7d50\u679c: 42\necho intval(42.3);    \/\/ \u7d50\u679c: 42\necho intval(42.5);    \/\/ \u7d50\u679c: 42 \uff08\u56db\u6368\u4e94\u5165\u3067\u306f\u306a\u3044\uff01\uff09\necho intval(42.9);    \/\/ \u7d50\u679c: 42\necho intval(-42.3);   \/\/ \u7d50\u679c: -42\necho intval(-42.9);   \/\/ \u7d50\u679c: -42\n<\/pre>\n\n\n\n<p><code>intval()<\/code>\u306f\u5e38\u306b0\u65b9\u5411\u3078\u306e\u4e38\u3081\u3092\u884c\u3044\u307e\u3059\u3002\u3053\u308c\u306f\u6b63\u306e\u6570\u3067\u306f\u4e0b\u3078\u306e\u5207\u308a\u6368\u3066\u3001\u8ca0\u306e\u6570\u3067\u306f\u4e0a\u3078\u306e\u5207\u308a\u4e0a\u3052\u306b\u306a\u308a\u307e\u3059\u3002\u3053\u306e\u6319\u52d5\u306f\u4ed6\u306e\u4e38\u3081\u95a2\u6570\u3068\u306f\u7570\u306a\u308b\u305f\u3081\u3001\u76ee\u7684\u306b\u5fdc\u3058\u3066\u9069\u5207\u306a\u95a2\u6570\u3092\u9078\u3076\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\uff1a<\/p>\n\n\n<div id=\"id-0d712781-af64-4dac-886e-1f89d448e3f2\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u95a2\u6570<\/th><th>42.5\u306e\u5834\u5408<\/th><th>-42.5\u306e\u5834\u5408<\/th><th>\u52d5\u4f5c<\/th><\/tr><\/thead><tbody><tr><td>intval()<\/td><td>42<\/td><td>-42<\/td><td>\u5c0f\u6570\u70b9\u4ee5\u4e0b\u3092\u5207\u308a\u6368\u3066\uff080\u65b9\u5411\uff09<\/td><\/tr><tr><td>round()<\/td><td>43<\/td><td>-43<\/td><td>\u56db\u6368\u4e94\u5165<\/td><\/tr><tr><td>ceil()<\/td><td>43<\/td><td>-42<\/td><td>\u5207\u308a\u4e0a\u3052\uff08\u4e0a\u65b9\u5411\uff09<\/td><\/tr><tr><td>floor()<\/td><td>42<\/td><td>-43<\/td><td>\u5207\u308a\u4e0b\u3052\uff08\u4e0b\u65b9\u5411\uff09<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u7279\u306b\u91d1\u984d\u8a08\u7b97\u3067\u306f\u3001\u7aef\u6570\u51e6\u7406\u306e\u65b9\u6cd5\u306b\u3088\u3063\u3066\u7d50\u679c\u304c\u5909\u308f\u3063\u3066\u304f\u308b\u305f\u3081\u3001\u30d3\u30b8\u30cd\u30b9\u30eb\u30fc\u30eb\u306b\u5fdc\u3058\u305f\u9069\u5207\u306a\u51e6\u7406\u304c\u5fc5\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5546\u54c1\u4fa1\u683c\u304b\u3089\u306e\u7a0e\u984d\u8a08\u7b97\uff08\u7a0e\u738710%\uff09\n$price = 123.45;\n$tax_rate = 0.1;\n$tax_amount = $price * $tax_rate; \/\/ 12.345\n\n\/\/ \u69d8\u3005\u306a\u4e38\u3081\u65b9\u6cd5\u306b\u3088\u308b\u7d50\u679c\n$tax_intval = intval($tax_amount);               \/\/ 12\uff08\u5207\u308a\u6368\u3066\uff09\n$tax_round = round($tax_amount);                 \/\/ 12\uff08\u56db\u6368\u4e94\u5165\uff09\n$tax_round_up = ceil($tax_amount);               \/\/ 13\uff08\u5207\u308a\u4e0a\u3052\uff09\n$tax_round_down = floor($tax_amount);            \/\/ 12\uff08\u5207\u308a\u4e0b\u3052\uff09\n$tax_round_precision = round($tax_amount, 2);    \/\/ 12.35\uff08\u5c0f\u6570\u70b9\u4ee5\u4e0b2\u6841\u3067\u56db\u6368\u4e94\u5165\uff09\n<\/pre>\n\n\n\n<p>\u307e\u305f\u3001\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u306e\u8a08\u7b97\u3067\u306f\u5fae\u5c0f\u306a\u8aa4\u5dee\u304c\u767a\u751f\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u3001\u3053\u308c\u304c<code>intval()<\/code>\u306e\u7d50\u679c\u306b\u5f71\u97ff\u3059\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6d6e\u52d5\u5c0f\u6570\u70b9\u8aa4\u5dee\u306e\u4f8b\n$result = 0.1 + 0.2;           \/\/ 0.30000000000000004\uff08\u53b3\u5bc6\u306b\u306f0.3\u3067\u306f\u306a\u3044\uff09\necho intval($result * 10);     \/\/ \u671f\u5f85\u5024: 3 \u5b9f\u969b\u306e\u7d50\u679c: 3\uff08\u3053\u306e\u4f8b\u3067\u306f\u554f\u984c\u306a\u3044\uff09\n\n\/\/ \u3088\u308a\u8907\u96d1\u306a\u8a08\u7b97\u3067\u306f\u4e88\u671f\u305b\u306c\u7d50\u679c\u306b\u306a\u308b\u53ef\u80fd\u6027\u3082\n$complex = (0.1 + 0.7) * 10;   \/\/ \u671f\u5f85\u5024: 8 \u5b9f\u969b\u306e\u5024: 7.9999999999999\necho intval($complex);         \/\/ 7\uff08\u671f\u5f85\u5024\u306f8\uff09\n<\/pre>\n\n\n\n<p>\u7cbe\u5ea6\u304c\u91cd\u8981\u306a\u8a08\u7b97\u3067\u306f\u3001\u6b21\u306e\u3088\u3046\u306a\u5bfe\u7b56\u304c\u6709\u52b9\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u4e38\u3081\u3092\u5148\u306b\u884c\u3046<\/strong>: <code>$value = 0.1 + 0.2; \/\/ 0.30000000000000004 echo intval(round($value * 10)); \/\/ 3\uff08\u671f\u5f85\u901a\u308a\u306e\u7d50\u679c\uff09<\/code><\/li>\n\n\n\n<li><strong>BCMath\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b<\/strong>\uff08\u9ad8\u7cbe\u5ea6\u6f14\u7b97\uff09: <code>$a = \"0.1\"; $b = \"0.2\"; $sum = bcadd($a, $b, 1); \/\/ \"0.3\"\uff08\u6587\u5b57\u5217\uff09 echo intval($sum * 10); \/\/ 3<\/code><\/li>\n\n\n\n<li><strong>\u91d1\u984d\u8a08\u7b97\u306f\u6700\u5c0f\u5358\u4f4d\uff08\u30bb\u30f3\u30c8\u7b49\uff09\u3067\u884c\u3046<\/strong>: <code>\/\/ \u30c9\u30eb\u30fb\u30bb\u30f3\u30c8\u8a08\u7b97\u306e\u4f8b $price_cents = 1995; \/\/ $19.95 $quantity = 3; $total_cents = $price_cents * $quantity; \/\/ 5985\u30bb\u30f3\u30c8 $total_dollars = $total_cents \/ 100; \/\/ $59.85<\/code><\/li>\n<\/ol>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u3067\u306f\u3001\u30d3\u30b8\u30cd\u30b9\u30ed\u30b8\u30c3\u30af\u306e\u8981\u4ef6\u306b\u5408\u308f\u305b\u3066\u9069\u5207\u306a\u4e38\u3081\u51e6\u7406\u3092\u9078\u629e\u3057\u3001<code>intval()<\/code>\u3092\u4f7f\u7528\u3059\u308b\u524d\u306b\u5fc5\u8981\u306a\u524d\u51e6\u7406\u3092\u884c\u3046\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-19\">\u914d\u5217\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308bintval()\u306e\u6319\u52d5\u3068\u5bfe\u51e6\u6cd5<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u57fa\u672c\u7684\u306b\u3001\u30b9\u30ab\u30e9\u30fc\u5024\uff08\u6574\u6570\u3001\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3001\u6587\u5b57\u5217\u3001\u30d6\u30fc\u30eb\u5024\uff09\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u305f\u3081\u306b\u8a2d\u8a08\u3055\u308c\u3066\u3044\u307e\u3059\u304c\u3001\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u9069\u7528\u3057\u305f\u5834\u5408\u306e\u6319\u52d5\u306f\u7279\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002\u3055\u3089\u306b\u3001PHP\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u52d5\u4f5c\u304c\u7570\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>PHP\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u308b\u6319\u52d5\u306e\u9055\u3044:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u914d\u5217\u306b\u5bfe\u3059\u308bintval()\n$array = [1, 2, 3];\n\n\/\/ PHP 7.3\u4ee5\u524d\necho intval($array); \/\/ \u7d50\u679c: 1\uff08\u8b66\u544a\u306a\u3057\uff09\n\n\/\/ PHP 7.4\u4ee5\u964d\necho intval($array); \/\/ Warning: Array to int conversion + \u7d50\u679c: 0\n<\/pre>\n\n\n\n<p>\u3053\u306e\u6319\u52d5\u306e\u5909\u66f4\u306f\u3001PHP 7.4\u3067\u5c0e\u5165\u3055\u308c\u305f\u578b\u30b7\u30b9\u30c6\u30e0\u306e\u53b3\u683c\u5316\u306b\u3088\u308b\u3082\u306e\u3067\u3059\u3002\u3064\u307e\u308a\u3001\u6700\u65b0\u306ePHP\u3067\u306f\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308b\u4e0d\u9069\u5207\u306a\u578b\u5909\u63db\u306b\u8b66\u544a\u3092\u767a\u3059\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f\u3002<\/p>\n\n\n\n<p><strong>\u914d\u5217\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092intval()\u306b\u6e21\u3059\u3079\u304d\u3067\u306a\u3044\u7406\u7531:<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u610f\u56f3\u304c\u4e0d\u660e\u78ba<\/strong>: \u914d\u5217\u5168\u4f53\u3092\u5358\u4e00\u306e\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u610f\u56f3\u306f\u307b\u3068\u3093\u3069\u306e\u5834\u5408\u4e0d\u660e\u78ba\u3067\u3001\u30d0\u30b0\u306e\u539f\u56e0\u306b\u306a\u308a\u307e\u3059<\/li>\n\n\n\n<li><strong>\u4e88\u6e2c\u4e0d\u80fd\u306a\u7d50\u679c<\/strong>: PHP\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u6319\u52d5\u304c\u7570\u306a\u308b\u305f\u3081\u3001\u79fb\u690d\u6027\u306e\u3042\u308b\u30b3\u30fc\u30c9\u304c\u66f8\u304d\u306b\u304f\u3044<\/li>\n\n\n\n<li><strong>\u8b66\u544a\u306e\u767a\u751f<\/strong>: PHP 7.4\u4ee5\u964d\u3067\u306f\u8b66\u544a\u304c\u767a\u751f\u3057\u3001\u30a8\u30e9\u30fc\u30ed\u30b0\u304c\u6c5a\u308c\u308b\u539f\u56e0\u306b\u306a\u308a\u307e\u3059<\/li>\n\n\n\n<li><strong>\u7121\u610f\u5473\u306a\u5909\u63db<\/strong>: \u8907\u5408\u30c7\u30fc\u30bf\u578b\u3092\u5358\u4e00\u306e\u6574\u6570\u5024\u306b\u5909\u63db\u3059\u308b\u3053\u3068\u306f\u901a\u5e38\u306f\u610f\u5473\u304c\u3042\u308a\u307e\u305b\u3093<\/li>\n<\/ol>\n\n\n\n<p><strong>\u63a8\u5968\u3055\u308c\u308b\u4ee3\u66ff\u30a2\u30d7\u30ed\u30fc\u30c1:<\/strong><\/p>\n\n\n\n<p>\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u51e6\u7406\u3059\u308b\u5834\u5408\u3001\u901a\u5e38\u306f\u500b\u3005\u306e\u8981\u7d20\u3084\u30d7\u30ed\u30d1\u30c6\u30a3\u306b\u5bfe\u3057\u3066<code>intval()<\/code>\u3092\u9069\u7528\u3059\u308b\u3079\u304d\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u914d\u5217\u306e\u5404\u8981\u7d20\u306b\u5bfe\u3059\u308bintval()\u306e\u9069\u7528\n$string_numbers = [\"1\", \"2\", \"3\", \"4abc\"];\n$integers = array_map('intval', $string_numbers);\n\/\/ \u7d50\u679c: [1, 2, 3, 4]\n\n\/\/ \u9023\u60f3\u914d\u5217\u306e\u7279\u5b9a\u306e\u30ad\u30fc\u306b\u5bfe\u3059\u308bintval()\u306e\u9069\u7528\n$product = [\n    'id' =&gt; \"1001\",\n    'name' =&gt; \"\u5546\u54c1A\",\n    'price' =&gt; \"1299\",\n    'stock' =&gt; \"5\"\n];\n\n\/\/ \u5fc5\u8981\u306a\u8981\u7d20\u3060\u3051\u3092\u6574\u6570\u306b\u5909\u63db\n$product_id = intval($product['id']);      \/\/ 1001\n$product_price = intval($product['price']); \/\/ 1299\n$product_stock = intval($product['stock']); \/\/ 5\n<\/pre>\n\n\n\n<p>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5834\u5408\u3082\u540c\u69d8\u306b\u3001\u500b\u3005\u306e\u30d7\u30ed\u30d1\u30c6\u30a3\u306b\u5bfe\u3057\u3066<code>intval()<\/code>\u3092\u9069\u7528\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$order = new stdClass();\n$order-&gt;id = \"12345\";\n$order-&gt;quantity = \"3\";\n\n\/\/ \u30d7\u30ed\u30d1\u30c6\u30a3\u3092\u500b\u5225\u306b\u5909\u63db\n$order_id = intval($order-&gt;id);         \/\/ 12345\n$order_quantity = intval($order-&gt;quantity); \/\/ 3\n<\/pre>\n\n\n\n<p><strong>\u578b\u30c1\u30a7\u30c3\u30af\u3068\u7d44\u307f\u5408\u308f\u305b\u305f\u5b89\u5168\u306a\u5b9f\u88c5:<\/strong><\/p>\n\n\n\n<p>\u578b\u306e\u5b89\u5168\u6027\u3092\u9ad8\u3081\u308b\u306b\u306f\u3001<code>is_array()<\/code>\u3084<code>is_object()<\/code>\u306a\u3069\u306e\u578b\u30c1\u30a7\u30c3\u30af\u95a2\u6570\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3092\u304a\u52e7\u3081\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u578b\u3092\u8003\u616e\u3057\u305f\u5b89\u5168\u306aintval\u95a2\u6570\nfunction safeIntval($value, $default = 0) {\n    if (is_array($value) || is_object($value)) {\n        return $default; \/\/ \u914d\u5217\/\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u8fd4\u3059\n    }\n    return intval($value);\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$value1 = safeIntval(\"42\");       \/\/ 42\n$value2 = safeIntval([1, 2, 3]);  \/\/ 0\uff08\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\uff09\n<\/pre>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u3067\u306f\u3001\u3053\u306e\u3088\u3046\u306b\u578b\u3092\u9069\u5207\u306b\u51e6\u7406\u3059\u308b\u3053\u3068\u3067\u30d0\u30b0\u3092\u4e88\u9632\u3057\u3001\u30e1\u30f3\u30c6\u30ca\u30f3\u30b9\u3057\u3084\u3059\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u7279\u306b\u30c1\u30fc\u30e0\u958b\u767a\u3084\u30e9\u30a4\u30d6\u30e9\u30ea\u958b\u767a\u3067\u306f\u3001\u3053\u3046\u3057\u305f\u5805\u7262\u306a\u30a2\u30d7\u30ed\u30fc\u30c1\u304c\u91cd\u8981\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-20\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6570\u5024\u51e6\u7406\u306b\u304a\u3051\u308b\u5b9f\u88c5\u4f8b<\/h3>\n\n\n\n<p>\u73fe\u4ee3\u306eWeb\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u3067\u306f\u3001\u5916\u90e8API\u3068\u306e\u9023\u643a\u306f\u4e0d\u53ef\u6b20\u3067\u3059\u3002\u3057\u304b\u3057\u3001API\u304b\u3089\u8fd4\u3055\u308c\u308b\u30c7\u30fc\u30bf\u306e\u578b\u306f\u5fc5\u305a\u3057\u3082\u7406\u60f3\u7684\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u7279\u306bJSON\u5f62\u5f0f\u306e\u30ec\u30b9\u30dd\u30f3\u30b9\u3067\u306f\u3001<strong>\u6570\u5024\u304c\u6587\u5b57\u5217\u3068\u3057\u3066<\/strong>\u8fd4\u3055\u308c\u308b\u3053\u3068\u304c\u975e\u5e38\u306b\u591a\u3044\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u5178\u578b\u7684\u306aAPI\u30ec\u30b9\u30dd\u30f3\u30b9\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">{\n  \"id\": \"1234567890\",\n  \"name\": \"\u30b9\u30de\u30fc\u30c8\u30d5\u30a9\u30f3A\",\n  \"price\": \"49999\",\n  \"stock\": \"42\",\n  \"categories\": [\"1\", \"5\", \"10\"],\n  \"ratings\": {\n    \"average\": \"4.5\",\n    \"count\": \"128\"\n  }\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306a\u30ec\u30b9\u30dd\u30f3\u30b9\u3092PHP\u3067\u51e6\u7406\u3059\u308b\u969b\u3001\u6570\u5024\u3068\u3057\u3066\u6271\u3046\u3079\u304d\u30d5\u30a3\u30fc\u30eb\u30c9\u306f<code>intval()<\/code>\u95a2\u6570\u3092\u4f7f\u3063\u3066\u660e\u793a\u7684\u306b\u5909\u63db\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ API\u30ec\u30b9\u30dd\u30f3\u30b9\u3092\u30c7\u30b3\u30fc\u30c9\n$response = file_get_contents('https:\/\/api.example.com\/products\/123');\n$data = json_decode($response, true);\n\n\/\/ \u6570\u5024\u30d5\u30a3\u30fc\u30eb\u30c9\u3092\u9069\u5207\u306b\u5909\u63db\n$product = [\n    'id' =&gt; intval($data['id']),\n    'name' =&gt; $data['name'],  \/\/ \u6587\u5b57\u5217\u306f\u305d\u306e\u307e\u307e\n    'price' =&gt; intval($data['price']),\n    'stock' =&gt; intval($data['stock']),\n    \/\/ \u914d\u5217\u5185\u306e\u8981\u7d20\u3082\u5909\u63db\n    'categories' =&gt; array_map('intval', $data['categories'])\n];\n\n\/\/ \u5909\u63db\u5f8c\u306f\u5b89\u5168\u306b\u6570\u5024\u6f14\u7b97\u304c\u53ef\u80fd\n$total_value = $product['price'] * $product['stock']; \/\/ 2,099,958\n<\/pre>\n\n\n\n<p>\u7279\u306b\u5927\u898f\u6a21\u306a\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306f\u3001\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u578b\u5909\u63db\u3092\u4e00\u8cab\u3057\u3066\u884c\u3046\u305f\u3081\u306e\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\u3092\u4f5c\u6210\u3059\u308b\u3068\u4fbf\u5229\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u578b\u5909\u63db\u3092\u884c\u3046\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\n * \n * @param array $data API\u30ec\u30b9\u30dd\u30f3\u30b9\u30c7\u30fc\u30bf\n * @param array $schema \u578b\u5b9a\u7fa9\u30b9\u30ad\u30fc\u30de\n * @return array \u578b\u5909\u63db\u5f8c\u306e\u30c7\u30fc\u30bf\n *\/\nfunction convertApiResponse($data, $schema) {\n    $result = [];\n    foreach ($schema as $key =&gt; $type) {\n        if (!isset($data[$key])) {\n            continue;\n        }\n        \n        switch ($type) {\n            case 'int':\n                $result[$key] = intval($data[$key]);\n                break;\n            case 'float':\n                $result[$key] = floatval($data[$key]);\n                break;\n            case 'bool':\n                $result[$key] = (bool) $data[$key];\n                break;\n            case 'int[]':\n                $result[$key] = array_map('intval', $data[$key]);\n                break;\n            default:\n                $result[$key] = $data[$key];\n        }\n    }\n    return $result;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$schema = [\n    'id' =&gt; 'int',\n    'name' =&gt; 'string',\n    'price' =&gt; 'int',\n    'stock' =&gt; 'int',\n    'categories' =&gt; 'int[]'\n];\n\n$product = convertApiResponse($data, $schema);\n<\/pre>\n\n\n\n<p>\u5b9f\u969b\u306e\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u3067\u306f\u3001\u6b21\u306e\u3088\u3046\u306a\u30b7\u30ca\u30ea\u30aa\u304c\u4e00\u822c\u7684\u3067\u3059\uff1a<\/p>\n\n\n\n<p><strong>\u4f8b1: \u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u51e6\u7406<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5546\u54c1\u4e00\u89a7API\u306e\u547c\u3073\u51fa\u3057\n$response = file_get_contents('https:\/\/api.example.com\/products?page=1');\n$data = json_decode($response, true);\n\n\/\/ \u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u60c5\u5831\u306e\u51e6\u7406\n$pagination = [\n    'current_page' =&gt; intval($data['meta']['current_page']),\n    'total_pages' =&gt; intval($data['meta']['total_pages']),\n    'per_page' =&gt; intval($data['meta']['per_page']),\n    'total' =&gt; intval($data['meta']['total'])\n];\n\n\/\/ \u6b21\u306e\u30da\u30fc\u30b8\u304c\u3042\u308b\u304b\u30c1\u30a7\u30c3\u30af\n$has_next_page = $pagination['current_page'] &lt; $pagination['total_pages'];\n<\/pre>\n\n\n\n<p><strong>\u4f8b2: \u6c7a\u6e08\u51e6\u7406<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6ce8\u6587\u30c7\u30fc\u30bf\u306e\u6e96\u5099\n$order_items = [\n    ['product_id' =&gt; intval($data['items'][0]['id']), 'quantity' =&gt; 2],\n    ['product_id' =&gt; intval($data['items'][1]['id']), 'quantity' =&gt; 1]\n];\n\n\/\/ API\u30ea\u30af\u30a8\u30b9\u30c8\u306e\u9001\u4fe1\n$response = sendApiRequest('POST', 'https:\/\/api.example.com\/orders', [\n    'customer_id' =&gt; intval($user['id']),\n    'items' =&gt; $order_items,\n    'total' =&gt; intval($cart_total)\n]);\n\n\/\/ \u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u51e6\u7406\n$order = json_decode($response, true);\n$order_id = intval($order['id']);\n<\/pre>\n\n\n\n<p>API\u30ec\u30b9\u30dd\u30f3\u30b9\u3092\u51e6\u7406\u3059\u308b\u969b\u306f\u3001\u4e00\u8cab\u3057\u305f\u578b\u5909\u63db\u3092\u884c\u3046\u3053\u3068\u3067\u3001\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5168\u4f53\u3067\u306e\u578b\u306e\u6574\u5408\u6027\u3092\u4fdd\u3061\u3001\u4e88\u671f\u305b\u306c\u30d0\u30b0\u3092\u9632\u6b62\u3067\u304d\u307e\u3059\u3002\u7279\u306b\u8907\u6570\u306e\u958b\u767a\u8005\u304c\u95a2\u308f\u308b\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306f\u3001\u3053\u306e\u3088\u3046\u306a\u30a2\u30d7\u30ed\u30fc\u30c1\u304c\u9577\u671f\u7684\u306a\u4fdd\u5b88\u6027\u3092\u9ad8\u3081\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-21\">intval() vs (int)\u30ad\u30e3\u30b9\u30c8 \u2013 \u77e5\u3063\u3066\u304a\u304f\u3079\u304d\u91cd\u8981\u306a\u9055\u3044<\/h2>\n\n\n\n<p>PHP\u3067\u306f\u6574\u6570\u3078\u306e\u5909\u63db\u65b9\u6cd5\u3068\u3057\u3066\u3001<code>intval()<\/code>\u95a2\u6570\u3068<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u6f14\u7b97\u5b50\u3068\u3044\u30462\u3064\u306e\u9078\u629e\u80a2\u304c\u3042\u308a\u307e\u3059\u3002\u4e00\u898b\u3059\u308b\u3068\u540c\u3058\u76ee\u7684\u3092\u679c\u305f\u3059\u3053\u308c\u3089\u3067\u3059\u304c\u3001\u5b9f\u969b\u306b\u306f\u91cd\u8981\u306a\u9055\u3044\u304c\u3042\u308a\u3001\u72b6\u6cc1\u306b\u5fdc\u3058\u305f\u9069\u5207\u306a\u4f7f\u3044\u5206\u3051\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u9055\u3044\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u52b9\u7387\u7684\u3067\u5b89\u5168\u306a\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002\u307e\u305a\u306f\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\u3092\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ intval()\u95a2\u6570\u3092\u4f7f\u3063\u305f\u5909\u63db\n$value1 = intval(\"42\");   \/\/ 42\n\n\/\/ (int)\u30ad\u30e3\u30b9\u30c8\u6f14\u7b97\u5b50\u3092\u4f7f\u3063\u305f\u5909\u63db\n$value2 = (int)\"42\";      \/\/ 42\n<\/pre>\n\n\n\n<p>\u4e00\u822c\u7684\u306a\u30b1\u30fc\u30b9\u3067\u306f\u540c\u3058\u7d50\u679c\u3092\u5f97\u3089\u308c\u307e\u3059\u304c\u3001\u4e21\u8005\u306b\u306f\u4f7f\u3044\u65b9\u3084\u6319\u52d5\u306b\u5fae\u5999\u306a\u9055\u3044\u304c\u3042\u308a\u307e\u3059\u3002\u6700\u3082\u91cd\u8981\u306a\u76f8\u9055\u70b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u57fa\u6570\u6307\u5b9a\u306e\u53ef\u5426<\/strong>\uff1a <code>intval()<\/code>\u306f\u7b2c2\u5f15\u6570\u3067\u57fa\u6570\uff082\u9032\u6570\u300116\u9032\u6570\u306a\u3069\uff09\u3092\u6307\u5b9a\u3067\u304d\u307e\u3059\u304c\u3001<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u306b\u306f\u3053\u306e\u6a5f\u80fd\u304c\u3042\u308a\u307e\u305b\u3093<\/li>\n\n\n\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9<\/strong>\uff1a <code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u306f\u8a00\u8a9e\u69cb\u9020\u3068\u3057\u3066\u5b9f\u88c5\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u4e00\u822c\u7684\u306b<code>intval()<\/code>\u3088\u308a\u3082\u9ad8\u901f\u3067\u3059<\/li>\n\n\n\n<li><strong>\u30d0\u30fc\u30b8\u30e7\u30f3\u9593\u306e\u6319\u52d5\u306e\u9055\u3044<\/strong>\uff1a \u7279\u306b\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5909\u63db\u306b\u304a\u3044\u3066\u3001PHP\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u6319\u52d5\u304c\u7570\u306a\u308a\u307e\u3059<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u9055\u3044\u306b\u3064\u3044\u3066\u3001\u3055\u3089\u306b\u8a73\u3057\u304f\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-22\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6bd4\u8f03 \u2013 \u3069\u3061\u3089\u304c\u9ad8\u901f\u3067\u30ea\u30bd\u30fc\u30b9\u52b9\u7387\u304c\u826f\u3044\u306e\u304b<\/h3>\n\n\n\n<p>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u89b3\u70b9\u3067\u306f\u3001<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u6f14\u7b97\u5b50\u306f<code>intval()<\/code>\u95a2\u6570\u3088\u308a\u3082<strong>\u660e\u3089\u304b\u306b\u9ad8\u901f<\/strong>\u3067\u3059\u3002\u3053\u308c\u306b\u306f\u6280\u8853\u7684\u306a\u7406\u7531\u304c\u3042\u308a\u307e\u3059\u3002<code>(int)<\/code>\u306f\u8a00\u8a9e\u69cb\u9020\uff08language construct\uff09\u3068\u3057\u3066\u5b9f\u88c5\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u95a2\u6570\u547c\u3073\u51fa\u3057\u306e\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u304c\u3042\u308a\u307e\u305b\u3093\u3002\u4e00\u65b9\u3001<code>intval()<\/code>\u306f\u901a\u5e38\u306ePHP\u95a2\u6570\u3067\u3042\u308a\u3001\u547c\u3073\u51fa\u3057\u3054\u3068\u306b\u5f15\u6570\u306e\u30b9\u30bf\u30c3\u30af\u64cd\u4f5c\u3084\u30b3\u30f3\u30c6\u30ad\u30b9\u30c8\u5207\u308a\u66ff\u3048\u306a\u3069\u306e\u51e6\u7406\u304c\u767a\u751f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u5b9f\u969b\u306e\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u30c6\u30b9\u30c8\u3067\u3053\u306e\u5dee\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\u3002\u4ee5\u4e0b\u306f100\u4e07\u56de\u306e\u6574\u6570\u5909\u63db\u3092\u884c\u3063\u305f\u5834\u5408\u306e\u51e6\u7406\u6642\u9593\u6bd4\u8f03\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ 100\u4e07\u56de\u306e\u5909\u63db\u51e6\u7406\u306e\u5b9f\u884c\u6642\u9593\u3092\u8a08\u6e2c\n$iterations = 1000000;\n$value = \"42\";\n\n\/\/ intval()\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6e2c\u5b9a\n$start = microtime(true);\nfor ($i = 0; $i &lt; $iterations; $i++) {\n    $result = intval($value);\n}\n$intval_time = microtime(true) - $start;\n\n\/\/ (int)\u30ad\u30e3\u30b9\u30c8\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6e2c\u5b9a\n$start = microtime(true);\nfor ($i = 0; $i &lt; $iterations; $i++) {\n    $result = (int)$value;\n}\n$cast_time = microtime(true) - $start;\n\necho \"intval(): \" . number_format($intval_time, 6) . \" \u79d2\\n\";\necho \"(int): \" . number_format($cast_time, 6) . \" \u79d2\\n\";\necho \"\u6bd4\u7387: \" . number_format($intval_time \/ $cast_time, 2) . \"\u500d\\n\";\n<\/pre>\n\n\n\n<p>\u69d8\u3005\u306a\u5165\u529b\u5024\u3067\u306e\u30c6\u30b9\u30c8\u7d50\u679c\u3092\u8868\u306b\u307e\u3068\u3081\u308b\u3068\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n<div id=\"id-508ca7f7-602c-4d37-939e-9990e8896562\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u5165\u529b\u30c7\u30fc\u30bf<\/th><th>intval()\u6642\u9593(\u79d2)<\/th><th>(int)\u6642\u9593(\u79d2)<\/th><th>\u901f\u5ea6\u5dee<\/th><\/tr><\/thead><tbody><tr><td>\u201c42\u201d<\/td><td>0.180<\/td><td>0.081<\/td><td>2.2\u500d<\/td><\/tr><tr><td>\u201c42abc\u201d<\/td><td>0.193<\/td><td>0.085<\/td><td>2.3\u500d<\/td><\/tr><tr><td>42.5<\/td><td>0.165<\/td><td>0.073<\/td><td>2.3\u500d<\/td><\/tr><tr><td>true<\/td><td>0.160<\/td><td>0.070<\/td><td>2.3\u500d<\/td><\/tr><tr><td>\u201c\u201d (\u7a7a\u6587\u5b57)<\/td><td>0.157<\/td><td>0.068<\/td><td>2.3\u500d<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u3053\u306e\u7d50\u679c\u304b\u3089\u3001<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u306f<code>intval()<\/code>\u3068\u6bd4\u8f03\u3057\u3066\u7d042.2\u301c2.3\u500d\u9ad8\u901f\u3067\u3042\u308b\u3053\u3068\u304c\u308f\u304b\u308a\u307e\u3059\u3002\u7279\u306b\u5927\u91cf\u306e\u30c7\u30fc\u30bf\u3092\u6271\u3046\u5834\u5408\u3084\u3001\u983b\u7e41\u306b\u578b\u5909\u63db\u3092\u884c\u3046\u30eb\u30fc\u30d7\u5185\u3067\u3053\u306e\u5dee\u306f\u9855\u8457\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u4f8b\u3048\u3070\u3001100\u4e07\u4ef6\u306e\u914d\u5217\u8981\u7d20\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u5834\u5408\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ 100\u4e07\u4ef6\u306e\u30c7\u30fc\u30bf\u306b\u5bfe\u3059\u308b\u51e6\u7406\n$data = array_fill(0, 1000000, \"42\");\n\n\/\/ intval()\u306b\u3088\u308b\u5909\u63db\n$start = microtime(true);\n$result1 = array_map('intval', $data);\n$intval_time = microtime(true) - $start;\n\n\/\/ (int)\u306b\u3088\u308b\u5909\u63db\n$start = microtime(true);\n$result2 = [];\nforeach ($data as $value) {\n    $result2[] = (int)$value;\n}\n$cast_time = microtime(true) - $start;\n\n\/\/ \u7d50\u679c: intval()\u306f\u7d040.8\u79d2\u3001(int)\u306f\u7d040.4\u79d2\n<\/pre>\n\n\n\n<p>\u305f\u3060\u3057\u3001\u3053\u306e\u6700\u9069\u5316\u304c\u91cd\u8981\u306b\u306a\u308b\u306e\u306f\u6b21\u306e\u3088\u3046\u306a\u5834\u5408\u306b\u9650\u3089\u308c\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5927\u898f\u6a21\u306a\u30eb\u30fc\u30d7<\/strong>\u5185\u3067\u306e\u5909\u63db\u51e6\u7406<\/li>\n\n\n\n<li><strong>\u9ad8\u983b\u5ea6<\/strong>\u3067\u547c\u3073\u51fa\u3055\u308c\u308b\u95a2\u6570\u5185\u3067\u306e\u5909\u63db<\/li>\n\n\n\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30af\u30ea\u30c6\u30a3\u30ab\u30eb<\/strong>\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u90e8\u5206<\/li>\n<\/ol>\n\n\n\n<p>\u4e00\u65b9\u3067\u3001<code>intval()<\/code>\u95a2\u6570\u306b\u306f\u57fa\u6570\u3092\u6307\u5b9a\u3067\u304d\u308b\u3068\u3044\u3046\u5229\u70b9\u304c\u3042\u308a\u307e\u3059\u3002\u57fa\u6570\u6307\u5b9a\u304c\u5fc5\u8981\u306a\u5834\u5408\u306f\u3001\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u5dee\u3088\u308a\u3082\u6a5f\u80fd\u6027\u3092\u512a\u5148\u3059\u3079\u304d\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u8003\u3048\u65b9\u3067\u30d0\u30e9\u30f3\u30b9\u3092\u53d6\u308b\u3068\u3088\u3044\u3067\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6a19\u6e96\u7684\u306a\u30b3\u30fc\u30c9\u3067\u306f\u8aad\u307f\u3084\u3059\u3055\u3092\u512a\u5148\u3057\u3001\u5fc5\u8981\u306b\u5fdc\u3058\u3066<code>intval()<\/code>\u3092\u4f7f\u7528<\/li>\n\n\n\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u306a\u90e8\u5206\u3084\u5927\u898f\u6a21\u306a\u30eb\u30fc\u30d7\u3067\u306f<code>(int)<\/code>\u3092\u691c\u8a0e<\/li>\n\n\n\n<li>\u30d7\u30ed\u30d5\u30a1\u30a4\u30ea\u30f3\u30b0\u3067\u5b9f\u969b\u306e\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u3092\u7279\u5b9a\u3057\u3066\u304b\u3089\u6700\u9069\u5316\u3092\u884c\u3046<\/li>\n<\/ul>\n\n\n\n<p>\u6700\u5f8c\u306b\u91cd\u8981\u306a\u70b9\u3068\u3057\u3066\u3001PHP\u958b\u767a\u306b\u304a\u3051\u308b\u4ed6\u306e\u6700\u9069\u5316\u624b\u6cd5\uff08\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u306e\u6539\u5584\u3001\u30ad\u30e3\u30c3\u30b7\u30e5\u5c0e\u5165\u306a\u3069\uff09\u3068\u6bd4\u8f03\u3059\u308b\u3068\u3001\u3053\u306e\u5dee\u306f\u6bd4\u8f03\u7684\u5c0f\u3055\u3044\u3053\u3068\u3092\u8a8d\u8b58\u3057\u3066\u304a\u304f\u3079\u304d\u3067\u3059\u3002\u307e\u305a\u306f\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u4e3b\u8981\u306a\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u306b\u5bfe\u51e6\u3059\u308b\u3053\u3068\u3092\u512a\u5148\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-23\">\u578b\u5909\u63db\u306e\u6319\u52d5\u306e\u9055\u3044\u3068\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u3067\u306e\u7d50\u679c\u306e\u5dee\u7570<\/h3>\n\n\n\n<p><code>intval()<\/code>\u3068<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u306f\u57fa\u672c\u7684\u306a\u5909\u63db\u3067\u306f\u540c\u69d8\u306e\u7d50\u679c\u3092\u8fd4\u3057\u307e\u3059\u304c\u3001\u3044\u304f\u3064\u304b\u306e\u91cd\u8981\u306a\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u3067\u306f\u6319\u52d5\u304c\u7570\u306a\u308a\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u9055\u3044\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u306f\u3001\u4e88\u671f\u305b\u306c\u30d0\u30b0\u3092\u9632\u3050\u305f\u3081\u306b\u975e\u5e38\u306b\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<p><strong>\u57fa\u672c\u7684\u306a\u578b\u5909\u63db\u3067\u306e\u5171\u901a\u70b9:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u57fa\u672c\u7684\u306a\u578b\u3067\u306f\u540c\u3058\u7d50\u679c\u306b\u306a\u308b\n$string = \"42\";      echo intval($string); \/\/ 42    echo (int)$string; \/\/ 42\n$mixed = \"42abc\";    echo intval($mixed);   \/\/ 42    echo (int)$mixed;   \/\/ 42\n$float = 42.75;      echo intval($float);   \/\/ 42    echo (int)$float;   \/\/ 42\n$bool = true;        echo intval($bool);    \/\/ 1     echo (int)$bool;    \/\/ 1\n$null = null;        echo intval($null);    \/\/ 0     echo (int)$null;    \/\/ 0\n<\/pre>\n\n\n\n<p><strong>\u6700\u3082\u91cd\u8981\u306a\u9055\u3044: \u57fa\u6570\u6307\u5b9a<\/strong><\/p>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306e\u6700\u5927\u306e\u7279\u5fb4\u306f\u57fa\u6570\uff08\u9032\u6570\uff09\u3092\u6307\u5b9a\u3067\u304d\u308b\u3053\u3068\u3067\u3059\u3002\u3053\u308c\u306f<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u306b\u306f\u306a\u3044\u6a5f\u80fd\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$hex = \"FF\";\necho intval($hex);      \/\/ 0\uff0810\u9032\u6570\u3068\u3057\u3066\u89e3\u91c8\u3059\u308b\u305f\u3081\uff09\necho intval($hex, 16);  \/\/ 255\uff0816\u9032\u6570\u3068\u3057\u3066\u89e3\u91c8\uff09\necho (int)$hex;         \/\/ 0\uff08\u5e38\u306b10\u9032\u6570\u3068\u3057\u3066\u89e3\u91c8\uff09\n\n$binary = \"1010\";\necho intval($binary);   \/\/ 1010\uff0810\u9032\u6570\u3068\u3057\u3066\u89e3\u91c8\uff09\necho intval($binary, 2); \/\/ 10\uff082\u9032\u6570\u3068\u3057\u3066\u89e3\u91c8\uff09\n<\/pre>\n\n\n\n<p>\u3053\u306e\u6a5f\u80fd\u306f16\u9032\u6570\u306e\u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u3084\u30d3\u30c3\u30c8\u64cd\u4f5c\u306a\u3069\u3001\u69d8\u3005\u306a\u5834\u9762\u3067\u5f79\u7acb\u3061\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u914d\u5217\u3068\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5909\u63db\u3067\u306ePHP\u30d0\u30fc\u30b8\u30e7\u30f3\u9593\u306e\u9055\u3044<\/strong><\/p>\n\n\n\n<p>\u7279\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u306a\u306e\u306f\u3001\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u5834\u5408\u3067\u3059\u3002\u3053\u306e\u6319\u52d5\u306fPHP\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u7570\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u914d\u5217\u306e\u5909\u63db\n$array = [1, 2, 3];\n\n\/\/ PHP 7.3\u4ee5\u524d\necho intval($array); \/\/ 1\necho (int)$array;    \/\/ 1\n\n\/\/ PHP 7.4\u4ee5\u964d\necho intval($array); \/\/ Warning: Array to int conversion + 0\necho (int)$array;    \/\/ Warning: Array to int conversion + 1\n<\/pre>\n\n\n\n<p>\u6ce8\u76ee\u3059\u3079\u304d\u306f\u3001PHP 7.4\u4ee5\u964d\u3067\u306f\u4e21\u65b9\u3068\u3082\u8b66\u544a\u3092\u767a\u3059\u308b\u3082\u306e\u306e\u3001<strong>\u8fd4\u3055\u308c\u308b\u5024\u304c\u7570\u306a\u308b<\/strong>\u70b9\u3067\u3059\u3002<code>intval()<\/code>\u306f0\u3092\u8fd4\u3057\u3001<code>(int)<\/code>\u306f1\u3092\u8fd4\u3057\u307e\u3059\u3002\u3053\u308c\u306f\u4e00\u8cab\u6027\u304c\u306a\u304f\u3001\u30d0\u30b0\u306e\u539f\u56e0\u306b\u306a\u308a\u3046\u308b\u9055\u3044\u3067\u3059\u3002<\/p>\n\n\n\n<p><strong>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5909\u63db\u3082\u540c\u69d8\u306b\u8907\u96d1\u3067\u3059\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6a19\u6e96\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\n$obj = new stdClass();\n\n\/\/ PHP 7.3\u4ee5\u524d\necho intval($obj); \/\/ 1\necho (int)$obj;    \/\/ 1\n\n\/\/ PHP 7.4\u4ee5\u964d\necho intval($obj); \/\/ Warning: Object of class stdClass to int conversion + 1\necho (int)$obj;    \/\/ Warning: Object of class stdClass to int conversion + 1\n<\/pre>\n\n\n\n<p>\u7279\u306b\u8907\u96d1\u306a\u306e\u306f<code>__toString()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u5b9f\u88c5\u3057\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5834\u5408\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class Number {\n    public function __toString() {\n        return \"42\";\n    }\n}\n$num = new Number();\n\n\/\/ PHP 7.2\u3067\u306f\u7570\u306a\u308b\u7d50\u679c\u306b\uff01\necho intval($num); \/\/ 1\necho (int)$num;    \/\/ 0\n\n\/\/ PHP 7.3\u3067\u306f\u540c\u3058\u7d50\u679c\u306b\necho intval($num); \/\/ 1\necho (int)$num;    \/\/ 1\n\n\/\/ PHP 7.4\u4ee5\u964d\u306f\u8b66\u544a\u4ed8\u304d\u3067\u540c\u3058\u7d50\u679c\necho intval($num); \/\/ Warning + 1\necho (int)$num;    \/\/ Warning + 1\n<\/pre>\n\n\n\n<p><strong>\u5b9f\u969b\u306e\u958b\u767a\u3067\u906d\u9047\u3057\u3084\u3059\u3044\u554f\u984c\u56de\u907f\u7b56<\/strong><\/p>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u9055\u3044\u3092\u8e0f\u307e\u3048\u3001\u5b9f\u969b\u306e\u958b\u767a\u3067\u306f\u4ee5\u4e0b\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u5fc3\u304c\u3051\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u578b\u30c1\u30a7\u30c3\u30af\u3092\u884c\u3063\u3066\u304b\u3089\u5909\u63db\u3059\u308b<\/strong>: <code>\/\/ \u5b89\u5168\u306a\u5909\u63db\u95a2\u6570 function safeIntval($value) { if (is_array($value) || is_object($value)) { return 0; \/\/ \u307e\u305f\u306f\u4f8b\u5916\u3092\u30b9\u30ed\u30fc } return intval($value); }<\/code><\/li>\n\n\n\n<li><strong>\u76ee\u7684\u306b\u5fdc\u3058\u305f\u9069\u5207\u306a\u65b9\u6cd5\u3092\u9078\u629e\u3059\u308b<\/strong>:\n<ul class=\"wp-block-list\">\n<li>\u57fa\u6570\u5909\u63db\u304c\u5fc5\u8981: <code>intval()<\/code>\u3092\u4f7f\u7528<\/li>\n\n\n\n<li>\u5358\u7d14\u306a\u6574\u6570\u5909\u63db: <code>(int)<\/code>\u3092\u4f7f\u7528\uff08\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u304c\u91cd\u8981\u306a\u5834\u5408\uff09<\/li>\n\n\n\n<li>\u660e\u793a\u7684\u306a\u30b3\u30fc\u30c9: <code>intval()<\/code>\u3092\u4f7f\u7528\uff08\u30b3\u30fc\u30c9\u306e\u610f\u56f3\u3092\u660e\u78ba\u306b\u3057\u305f\u3044\u5834\u5408\uff09<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u7279\u6b8a\u306a\u30b1\u30fc\u30b9\u3067\u306f\u5c02\u7528\u306e\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b<\/strong>:\n<ul class=\"wp-block-list\">\n<li>16\u9032\u6570\u5909\u63db: <code>hexdec()<\/code><\/li>\n\n\n\n<li>2\u9032\u6570\u5909\u63db: <code>bindec()<\/code><\/li>\n\n\n\n<li>8\u9032\u6570\u5909\u63db: <code>octdec()<\/code><\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306a\u9055\u3044\u3092\u7406\u89e3\u3057\u3001\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u4e00\u8cab\u3057\u305f\u65b9\u6cd5\u3092\u63a1\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u30d0\u30b0\u306e\u767a\u751f\u3092\u6e1b\u3089\u3057\u3001\u30e1\u30f3\u30c6\u30ca\u30f3\u30b9\u3057\u3084\u3059\u3044\u30b3\u30fc\u30c9\u304c\u66f8\u3051\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-24\">intval()\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af<\/h2>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u4fbf\u5229\u3067\u591a\u6a5f\u80fd\u3067\u3059\u304c\u3001\u5927\u898f\u6a21\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3084\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u306a\u5834\u9762\u3067\u306f\u3001\u305d\u306e\u4f7f\u3044\u65b9\u3092\u6700\u9069\u5316\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u7279\u306b\u5927\u91cf\u306e\u30c7\u30fc\u30bf\u3092\u51e6\u7406\u3059\u308b\u5834\u9762\u3084\u9ad8\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\u306eWeb\u30b5\u30a4\u30c8\u3067\u306f\u3001\u5c0f\u3055\u306a\u6700\u9069\u5316\u306e\u7a4d\u307f\u91cd\u306d\u304c\u5927\u304d\u306a\u9055\u3044\u3092\u751f\u307f\u307e\u3059\u3002<\/p>\n\n\n\n<p><code>intval()<\/code>\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306b\u5f71\u97ff\u3059\u308b\u4e3b\u306a\u8981\u56e0\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u95a2\u6570\u547c\u3073\u51fa\u3057\u306e\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9<\/strong> \u2013 PHP\u306e\u95a2\u6570\u547c\u3073\u51fa\u3057\u306b\u306f\u57fa\u672c\u7684\u306a\u30b3\u30b9\u30c8\u304c\u304b\u304b\u308a\u307e\u3059<\/li>\n\n\n\n<li><strong>\u57fa\u6570\u6307\u5b9a\u51e6\u7406<\/strong> \u2013 \u7b2c2\u5f15\u6570\u3092\u4f7f\u7528\u3059\u308b\u3068\u8ffd\u52a0\u306e\u51e6\u7406\u30b3\u30b9\u30c8\u304c\u767a\u751f\u3057\u307e\u3059<\/li>\n\n\n\n<li><strong>\u6587\u5b57\u5217\u89e3\u6790<\/strong> \u2013 \u7279\u306b\u9577\u3044\u6587\u5b57\u5217\u3084\u8907\u96d1\u306a\u6587\u5b57\u5217\u3092\u51e6\u7406\u3059\u308b\u5834\u5408\u3001\u89e3\u6790\u30b3\u30b9\u30c8\u304c\u5897\u52a0\u3057\u307e\u3059<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u8981\u56e0\u3092\u8003\u616e\u3057\u3001\u52b9\u7387\u7684\u306a\u6574\u6570\u5909\u63db\u3092\u5b9f\u73fe\u3059\u308b\u305f\u3081\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-25\">\u4e0d\u5fc5\u8981\u306a\u578b\u5909\u63db\u3092\u907f\u3051\u308b\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u30d1\u30bf\u30fc\u30f3<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u6700\u9069\u5316\u3059\u308b\u306b\u306f\u3001\u307e\u305a\u4e0d\u5fc5\u8981\u306a\u578b\u5909\u63db\u3092\u6392\u9664\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u4e00\u898b\u4e9b\u7d30\u306b\u601d\u3048\u308b\u3053\u308c\u3089\u306e\u5909\u63db\u3082\u3001\u5927\u91cf\u306b\u5b9f\u884c\u3055\u308c\u308b\u3068\u7121\u8996\u3067\u304d\u306a\u3044\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>1. \u65e9\u671f\u5909\u63db\u30d1\u30bf\u30fc\u30f3<\/strong><\/p>\n\n\n\n<p>\u5909\u6570\u3092\u4f7f\u7528\u3059\u308b\u524d\u306b\u3001\u3067\u304d\u308b\u3060\u3051\u65e9\u3044\u6bb5\u968e\u3067\u9069\u5207\u306a\u578b\u306b\u5909\u63db\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u975e\u52b9\u7387\u306a\u4f8b\nfunction calculateTotal($price, $quantity) {\n    return intval($price) * intval($quantity); \/\/ \u95a2\u6570\u5185\u3067\u6bce\u56de\u5909\u63db\n}\n\n\/\/ \u52b9\u7387\u7684\u306a\u4f8b\nfunction calculateTotal($price, $quantity) {\n    \/\/ \u95a2\u6570\u306e\u5148\u982d\u3067\u4e00\u5ea6\u3060\u3051\u5909\u63db\n    $price_int = intval($price);\n    $quantity_int = intval($quantity);\n    return $price_int * $quantity_int;\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u65b9\u6cd5\u306f\u7279\u306b\u518d\u5229\u7528\u3055\u308c\u308b\u5024\u306b\u52b9\u679c\u7684\u3067\u3059\u3002\u4e00\u5ea6\u5909\u63db\u3057\u305f\u3089\u305d\u306e\u7d50\u679c\u3092\u518d\u5229\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u4f59\u5206\u306a\u51e6\u7406\u3092\u6e1b\u3089\u305b\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>2. \u540c\u3058\u5024\u306e\u7e70\u308a\u8fd4\u3057\u5909\u63db\u3092\u9632\u3050<\/strong><\/p>\n\n\n\n<p>\u540c\u3058\u5024\u306b\u5bfe\u3057\u3066\u8907\u6570\u56de<code>intval()<\/code>\u3092\u547c\u3073\u51fa\u3059\u3068\u3001\u7121\u99c4\u306a\u51e6\u7406\u304c\u767a\u751f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u975e\u52b9\u7387\u306a\u4f8b\nif (intval($value) &gt; 0) {\n    $result = intval($value) * 2; \/\/ \u540c\u3058\u5024\u3092\u518d\u5ea6\u5909\u63db\n    $total += intval($value);     \/\/ \u3055\u3089\u306b\u540c\u3058\u5024\u3092\u5909\u63db\n}\n\n\/\/ \u52b9\u7387\u7684\u306a\u4f8b\n$value_int = intval($value); \/\/ \u4e00\u5ea6\u3060\u3051\u5909\u63db\nif ($value_int &gt; 0) {\n    $result = $value_int * 2;\n    $total += $value_int;\n}\n<\/pre>\n\n\n\n<p><strong>3. \u30eb\u30fc\u30d7\u5185\u3067\u306e\u6700\u9069\u5316<\/strong><\/p>\n\n\n\n<p>\u30eb\u30fc\u30d7\u306e\u4e2d\u3067\u540c\u3058\u5024\u3092\u4f55\u5ea6\u3082\u5909\u63db\u3057\u306a\u3044\u3088\u3046\u306b\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u975e\u52b9\u7387\u306a\u4f8b\nforeach ($items as $item) {\n    if (intval($item['quantity']) &gt; 0) {\n        $total += intval($item['price']) * intval($item['quantity']);\n    }\n}\n\n\/\/ \u52b9\u7387\u7684\u306a\u4f8b\nforeach ($items as $item) {\n    $quantity = intval($item['quantity']);\n    if ($quantity &gt; 0) {\n        $price = intval($item['price']);\n        $total += $price * $quantity;\n    }\n}\n<\/pre>\n\n\n\n<p><strong>4. \u30c7\u30fc\u30bf\u306e\u524d\u51e6\u7406<\/strong><\/p>\n\n\n\n<p>\u7279\u306b\u8907\u6570\u306e\u64cd\u4f5c\u304c\u5fc5\u8981\u306a\u30c7\u30fc\u30bf\u30bb\u30c3\u30c8\u3067\u306f\u3001\u5148\u306b\u4e00\u62ec\u3067\u578b\u5909\u63db\u3092\u884c\u3044\u3001\u305d\u306e\u5f8c\u306e\u51e6\u7406\u3067\u306f\u5909\u63db\u6e08\u307f\u306e\u30c7\u30fc\u30bf\u3092\u4f7f\u7528\u3059\u308b\u3068\u3088\u308a\u52b9\u7387\u7684\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u52b9\u7387\u7684\u306a\u30c7\u30fc\u30bf\u524d\u51e6\u7406\u30d1\u30bf\u30fc\u30f3\n$products = fetchProductsFromDatabase();\n\n\/\/ \u3059\u3079\u3066\u306e\u6570\u5024\u30d5\u30a3\u30fc\u30eb\u30c9\u3092\u4e00\u5ea6\u3060\u3051\u5909\u63db\nforeach ($products as &amp;$product) {\n    $product['id'] = intval($product['id']);\n    $product['price'] = intval($product['price']);\n    $product['stock'] = intval($product['stock']);\n}\n\n\/\/ \u4ee5\u964d\u306e\u51e6\u7406\u3067\u306f\u5909\u63db\u6e08\u307f\u306e\u5024\u3092\u4f7f\u7528\nforeach ($products as $product) {\n    if ($product['stock'] &gt; 0) {\n        $value = $product['price'] * $product['stock'];\n        \/\/ \u51e6\u7406\u7d9a\u884c...\n    }\n}\n<\/pre>\n\n\n\n<p><strong>5. \u914d\u5217\u64cd\u4f5c\u306e\u6700\u9069\u5316<\/strong><\/p>\n\n\n\n<p>\u914d\u5217\u306e\u8981\u7d20\u3092\u4e00\u62ec\u5909\u63db\u3059\u308b\u5834\u5408\u306f\u3001<code>array_map()<\/code>\u3068<code>array_column()<\/code>\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3068\u52b9\u7387\u7684\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u975e\u52b9\u7387\u306a\u4f8b\n$ids = [];\nforeach ($items as $item) {\n    $ids[] = intval($item['id']);\n}\n\n\/\/ \u52b9\u7387\u7684\u306a\u4f8b\uff08array_map\u306fC\u8a00\u8a9e\u5b9f\u88c5\u3067\u9ad8\u901f\uff09\n$ids = array_map('intval', array_column($items, 'id'));\n<\/pre>\n\n\n\n<p><strong>6. \u578b\u30d2\u30f3\u30c8\u306e\u6d3b\u7528<\/strong><\/p>\n\n\n\n<p>PHP 7\u4ee5\u964d\u3067\u306f\u3001\u578b\u30d2\u30f3\u30c8\u3092\u4f7f\u3063\u3066\u81ea\u52d5\u7684\u306a\u578b\u5909\u63db\u3092\u6d3b\u7528\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PHP 7\u4ee5\u964d\u306e\u578b\u30d2\u30f3\u30c8\nfunction processOrder(int $product_id, int $quantity): int {\n    return $product_id * $quantity;\n}\n\n\/\/ \u547c\u3073\u51fa\u3057\u6642\u306b\u660e\u793a\u7684\u306b\u5909\u63db\n$total = processOrder((int)$_POST['product_id'], (int)$_POST['quantity']);\n<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d1\u30bf\u30fc\u30f3\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u3067\u3001<code>intval()<\/code>\u306e\u4f7f\u7528\u983b\u5ea6\u3092\u6e1b\u3089\u3057\u3001\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5168\u4f53\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u5411\u4e0a\u3055\u305b\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u904e\u5ea6\u306a\u6700\u9069\u5316\u3088\u308a\u3082\u30b3\u30fc\u30c9\u306e\u53ef\u8aad\u6027\u3092\u512a\u5148\u3059\u308b\u3053\u3068\u3082\u91cd\u8981\u3067\u3059\u3002\u7279\u306b\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u3067\u306a\u3044\u90e8\u5206\u3067\u306f\u3001\u660e\u78ba\u3055\u3092\u72a0\u7272\u306b\u3057\u3066\u307e\u3067\u6700\u9069\u5316\u3092\u884c\u3046\u5fc5\u8981\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-26\">\u5927\u898f\u6a21\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306e\u52b9\u7387\u7684\u306a\u6574\u6570\u5909\u63db\u6226\u7565<\/h3>\n\n\n\n<p>\u5927\u898f\u6a21\u306aPHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306f\u3001\u30c7\u30fc\u30bf\u306e\u578b\u5909\u63db\u3092\u4f53\u7cfb\u7684\u306b\u7ba1\u7406\u3059\u308b\u3053\u3068\u304c\u975e\u5e38\u306b\u91cd\u8981\u3067\u3059\u3002\u591a\u304f\u306e\u30c7\u30fc\u30bf\u30bd\u30fc\u30b9\u304b\u3089\u306e\u5165\u529b\u3001\u8907\u6570\u306e\u958b\u767a\u8005\u306e\u30b3\u30fc\u30c9\u3001\u8907\u96d1\u306a\u30c7\u30fc\u30bf\u69cb\u9020\u304c\u7d61\u307f\u5408\u3046\u74b0\u5883\u3067\u306f\u3001\u4e00\u8cab\u3057\u305f\u578b\u5909\u63db\u6226\u7565\u304c\u30b3\u30fc\u30c9\u306e\u54c1\u8cea\u3068\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u5927\u304d\u304f\u5de6\u53f3\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u30c7\u30fc\u30bf\u30d5\u30ed\u30fc\u306b\u6cbf\u3063\u305f\u578b\u5909\u63db\u30a2\u30d7\u30ed\u30fc\u30c1<\/strong><\/p>\n\n\n\n<p>\u52b9\u7387\u7684\u306a\u578b\u5909\u63db\u6226\u7565\u306e\u6838\u5fc3\u306f\u3001\u300c\u30c7\u30fc\u30bf\u306e\u5165\u53e3\u3067\u5909\u63db\u3057\u3001\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5185\u3067\u306f\u578b\u3092\u4e00\u8cab\u3055\u305b\u308b\u300d\u3068\u3044\u3046\u539f\u5247\u3067\u3059\u3002\u5177\u4f53\u7684\u306b\u306f\u4ee5\u4e0b\u306e4\u3064\u306e\u30dd\u30a4\u30f3\u30c8\u306b\u6ce8\u76ee\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u5165\u53e3\u3067\u306e\u5909\u63db<\/strong>: HTTP\u30ea\u30af\u30a8\u30b9\u30c8\u3001API\u5165\u529b\u3001\u30d5\u30a1\u30a4\u30eb\u30a4\u30f3\u30dd\u30fc\u30c8\u306a\u3069<\/li>\n\n\n\n<li><strong>\u30c7\u30fc\u30bf\u30a2\u30af\u30bb\u30b9\u5c64\u3067\u306e\u578b\u4fdd\u8a3c<\/strong>: \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u306e\u53d6\u5f97\u7d50\u679c\u306e\u5909\u63db<\/li>\n\n\n\n<li><strong>\u30c9\u30e1\u30a4\u30f3\u30e2\u30c7\u30eb\u3067\u306e\u578b\u306e\u4e00\u8cab\u6027<\/strong>: \u30a8\u30f3\u30c6\u30a3\u30c6\u30a3\u3084\u30b5\u30fc\u30d3\u30b9\u5c64\u3067\u306e\u578b\u7ba1\u7406<\/li>\n\n\n\n<li><strong>\u51fa\u529b\u524d\u306e\u578b\u78ba\u8a8d<\/strong>: API\u30ec\u30b9\u30dd\u30f3\u30b9\u3084\u30d3\u30e5\u30fc\u3078\u306e\u30c7\u30fc\u30bf\u63d0\u4f9b\u524d<\/li>\n<\/ol>\n\n\n\n<p><strong>\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3: \u30ea\u30af\u30a8\u30b9\u30c8\u30d0\u30ea\u30c7\u30fc\u30bf<\/strong><\/p>\n\n\n\n<p>\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3078\u306e\u5165\u529b\u3092\u4e00\u5143\u7ba1\u7406\u3059\u308b\u30ea\u30af\u30a8\u30b9\u30c8\u30d0\u30ea\u30c7\u30fc\u30bf\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u3067\u3001\u578b\u5909\u63db\u306e\u6574\u5408\u6027\u3092\u78ba\u4fdd\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class TypedRequestValidator {\n    public function validate(array $input, array $schema): array {\n        $validated = [];\n        foreach ($schema as $field =&gt; $rule) {\n            if (!isset($input[$field])) {\n                continue;\n            }\n            \n            $value = $input[$field];\n            \n            if ($rule === 'int') {\n                $validated[$field] = intval($value);\n            } elseif ($rule === 'float') {\n                $validated[$field] = floatval($value);\n            } elseif ($rule === 'bool') {\n                $validated[$field] = (bool) $value;\n            } else {\n                $validated[$field] = $value;\n            }\n        }\n        return $validated;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$validator = new TypedRequestValidator();\n$data = $validator-&gt;validate($_POST, [\n    'product_id' =&gt; 'int',\n    'quantity' =&gt; 'int',\n    'price' =&gt; 'float'\n]);\n\n\/\/ \u4ee5\u964d\u306e\u51e6\u7406\u3067\u306f$data\u306e\u578b\u306f\u4fdd\u8a3c\u3055\u308c\u3066\u3044\u308b\n<\/pre>\n\n\n\n<p><strong>\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3: \u30a8\u30f3\u30c6\u30a3\u30c6\u30a3\u30af\u30e9\u30b9<\/strong><\/p>\n\n\n\n<p>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u8a2d\u8a08\u3067\u306f\u3001\u30a8\u30f3\u30c6\u30a3\u30c6\u30a3\u30af\u30e9\u30b9\u5185\u3067\u578b\u5909\u63db\u3092\u96c6\u4e2d\u7ba1\u7406\u3059\u308b\u3053\u3068\u304c\u52b9\u679c\u7684\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class Product {\n    private int $id;\n    private string $name;\n    private int $stock;\n    \n    public function __construct(array $data) {\n        \/\/ \u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3067\u578b\u3092\u4fdd\u8a3c\n        $this-&gt;id = intval($data['id'] ?? 0);\n        $this-&gt;name = (string)($data['name'] ?? '');\n        $this-&gt;stock = intval($data['stock'] ?? 0);\n    }\n    \n    \/\/ \u578b\u30d2\u30f3\u30c8\u306b\u3088\u308b\u623b\u308a\u5024\u306e\u578b\u4fdd\u8a3c\n    public function getId(): int {\n        return $this-&gt;id;\n    }\n    \n    public function getName(): string {\n        return $this-&gt;name;\n    }\n    \n    public function getStock(): int {\n        return $this-&gt;stock;\n    }\n}\n<\/pre>\n\n\n\n<p><strong>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u7d50\u679c\u306e\u52b9\u7387\u7684\u306a\u578b\u5909\u63db<\/strong><\/p>\n\n\n\n<p>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u7d50\u679c\u30bb\u30c3\u30c8\u306e\u578b\u5909\u63db\u3082\u4f53\u7cfb\u7684\u306b\u884c\u3044\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class ResultTypeConverter {\n    public static function convertResultSet(array $rows, array $integerFields): array {\n        foreach ($rows as &amp;$row) {\n            foreach ($integerFields as $field) {\n                if (isset($row[$field])) {\n                    $row[$field] = intval($row[$field]);\n                }\n            }\n        }\n        return $rows;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$results = $db-&gt;query(\"SELECT id, name, price, stock FROM products\")-&gt;fetchAll();\n$products = ResultTypeConverter::convertResultSet($results, ['id', 'stock']);\n<\/pre>\n\n\n\n<p><strong>\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u306e\u578b\u5909\u63db\u6a5f\u80fd\u306e\u6d3b\u7528<\/strong><\/p>\n\n\n\n<p>\u591a\u304f\u306ePHP\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u306f\u578b\u5909\u63db\u306e\u305f\u3081\u306e\u7d44\u307f\u8fbc\u307f\u6a5f\u80fd\u3092\u63d0\u4f9b\u3057\u3066\u3044\u307e\u3059\u3002\u4f8b\u3048\u3070Laravel\u3067\u306f\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ Laravel\u30e2\u30c7\u30eb\u306e\u30ad\u30e3\u30b9\u30c8\u6a5f\u80fd\nclass Product extends Model {\n    protected $casts = [\n        'id' =&gt; 'integer',\n        'price' =&gt; 'float',\n        'stock' =&gt; 'integer',\n        'is_active' =&gt; 'boolean'\n    ];\n}\n<\/pre>\n\n\n\n<p><strong>\u8907\u96d1\u306a\u30cd\u30b9\u30c8\u3055\u308c\u305f\u30c7\u30fc\u30bf\u69cb\u9020\u306e\u51e6\u7406<\/strong><\/p>\n\n\n\n<p>API\u30ec\u30b9\u30dd\u30f3\u30b9\u306a\u3069\u8907\u96d1\u306a\u30cd\u30b9\u30c8\u3055\u308c\u305f\u30c7\u30fc\u30bf\u69cb\u9020\u3092\u51e6\u7406\u3059\u308b\u305f\u3081\u306e\u6c4e\u7528\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u3082\u6709\u7528\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class NestedTypeConverter {\n    public static function convert(array $data, array $schema): array {\n        $result = [];\n        foreach ($schema as $key =&gt; $type) {\n            if (!isset($data[$key])) {\n                continue;\n            }\n            \n            \/\/ \u914d\u5217\u8981\u7d20\u306e\u4e00\u62ec\u5909\u63db\n            if ($type === 'int[]' &amp;&amp; is_array($data[$key])) {\n                $result[$key] = array_map('intval', $data[$key]);\n            } \n            \/\/ \u5358\u4e00\u5024\u306e\u5909\u63db\n            elseif ($type === 'int') {\n                $result[$key] = intval($data[$key]);\n            } \n            \/\/ \u305d\u306e\u4ed6\u306e\u578b...\n            else {\n                $result[$key] = $data[$key];\n            }\n        }\n        return $result;\n    }\n}\n<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6226\u7565\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u5927\u898f\u6a21\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306b\u304a\u3044\u3066\u3082\u4e00\u8cab\u3057\u305f\u578b\u306e\u7ba1\u7406\u304c\u53ef\u80fd\u306b\u306a\u308a\u3001\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u5411\u4e0a\u3068\u30d0\u30b0\u306e\u6e1b\u5c11\u306b\u3064\u306a\u304c\u308a\u307e\u3059\u3002\u7279\u306b\u8907\u6570\u306e\u958b\u767a\u8005\u304c\u95a2\u308f\u308b\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306f\u3001\u3053\u3046\u3057\u305f\u4f53\u7cfb\u7684\u306a\u30a2\u30d7\u30ed\u30fc\u30c1\u304c\u9577\u671f\u7684\u306a\u4fdd\u5b88\u6027\u3092\u9ad8\u3081\u308b\u9375\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-27\">intval()\u3067\u767a\u751f\u3057\u304c\u3061\u306a5\u3064\u306e\u843d\u3068\u3057\u7a74\u3068\u89e3\u6c7a\u7b56<\/h2>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u4e00\u898b\u30b7\u30f3\u30d7\u30eb\u3067\u5b89\u5168\u306b\u601d\u3048\u307e\u3059\u304c\u3001\u7279\u5b9a\u306e\u72b6\u6cc1\u3067\u306f\u4e88\u671f\u305b\u306c\u52d5\u4f5c\u3092\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u7d4c\u9a13\u8c4a\u5bcc\u306a\u958b\u767a\u8005\u3067\u3082\u30cf\u30de\u308a\u304c\u3061\u306a\u843d\u3068\u3057\u7a74\u3068\u3001\u305d\u306e\u89e3\u6c7a\u7b56\u306b\u3064\u3044\u3066\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<p>\u4ee5\u4e0b\u306b\u53d6\u308a\u4e0a\u3052\u308b\u554f\u984c\u306f\u3001\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u983b\u7e41\u306b\u906d\u9047\u3059\u308b\u3082\u306e\u3070\u304b\u308a\u3067\u3059\u3002\u3053\u308c\u3089\u306e\u843d\u3068\u3057\u7a74\u3092\u7406\u89e3\u3057\u3001\u9069\u5207\u306a\u5bfe\u7b56\u3092\u8b1b\u3058\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5805\u7262\u306aPHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u69cb\u7bc9\u3067\u304d\u308b\u3067\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-28\">32\u30d3\u30c3\u30c8\u74b0\u5883\u306864\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306e\u6319\u52d5\u306e\u9055\u3044\u306b\u6ce8\u610f<\/h3>\n\n\n\n<p>PHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u7570\u306a\u308b\u30b5\u30fc\u30d0\u30fc\u74b0\u5883\u306b\u30c7\u30d7\u30ed\u30a4\u3059\u308b\u969b\u306b\u898b\u843d\u3068\u3057\u304c\u3061\u306a\u306e\u304c\u300132\u30d3\u30c3\u30c8\u74b0\u5883\u306864\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306e\u6574\u6570\u51e6\u7406\u306e\u9055\u3044\u3067\u3059\u3002\u7279\u306b<code>intval()<\/code>\u95a2\u6570\u306f\u3001\u3053\u306e\u74b0\u5883\u5dee\u7570\u306e\u5f71\u97ff\u3092\u76f4\u63a5\u53d7\u3051\u308b\u305f\u3081\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<p><strong>\u6574\u6570\u306e\u6700\u5927\u5024\u306e\u9055\u3044:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u74b0\u5883\u306b\u3088\u3063\u3066\u7570\u306a\u308b\u6574\u6570\u306e\u6700\u5927\u5024\necho PHP_INT_MAX; \n\/\/ 32\u30d3\u30c3\u30c8\u74b0\u5883: 2147483647\uff08\u7d0421\u5104\uff09\n\/\/ 64\u30d3\u30c3\u30c8\u74b0\u5883: 9223372036854775807\uff08\u7d04922\u4eac\uff09\n<\/pre>\n\n\n\n<p>\u3053\u306e\u5dee\u304c<code>intval()<\/code>\u306e\u6319\u52d5\u306b\u5f71\u97ff\u3059\u308b\u306e\u306f\u3001\u74b0\u5883\u306e\u6574\u6570\u4e0a\u9650\u3092\u8d85\u3048\u308b\u5024\u3092\u5909\u63db\u3057\u3088\u3046\u3068\u3057\u305f\u3068\u304d\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ 32\u30d3\u30c3\u30c8\u74b0\u5883\u306e\u6700\u5927\u5024\u3092\u8d85\u3048\u308b\u5024\n$large_id = \"2500000000\"; \/\/ 25\u5104\necho intval($large_id);\n\/\/ 32\u30d3\u30c3\u30c8\u74b0\u5883: 2147483647\uff08\u6700\u5927\u5024\u306b\u5207\u308a\u8a70\u3081\uff09\n\/\/ 64\u30d3\u30c3\u30c8\u74b0\u5883: 2500000000\uff08\u6b63\u78ba\u306a\u5024\uff09\n<\/pre>\n\n\n\n<p><strong>\u5b9f\u969b\u306b\u554f\u984c\u304c\u767a\u751f\u3059\u308b\u30b7\u30ca\u30ea\u30aa:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u5927\u304d\u306aID\u5024\u3092\u53d6\u5f97\n$record_id = \"2500000000\"; \/\/ \u6587\u5b57\u5217\u3068\u3057\u3066\u53d6\u5f97\n$id = intval($record_id); \/\/ \u6574\u6570\u306b\u5909\u63db\n\n\/\/ \u6b21\u306e\u3088\u3046\u306a\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u3092\u5b9f\u884c\n$query = \"SELECT * FROM large_table WHERE id = $id\";\n\/\/ 32\u30d3\u30c3\u30c8\u74b0\u5883: id = 2147483647\uff08\u9593\u9055\u3063\u305f\u5024\uff09\u3067\u691c\u7d22\n\/\/ 64\u30d3\u30c3\u30c8\u74b0\u5883: id = 2500000000\uff08\u6b63\u3057\u3044\u5024\uff09\u3067\u691c\u7d22\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306a\u4e0d\u4e00\u81f4\u306f\u3001\u958b\u767a\u74b0\u5883\uff08\u591a\u304f\u306e\u5834\u540864\u30d3\u30c3\u30c8\uff09\u3068\u672c\u756a\u74b0\u5883\uff08\u53e4\u3044\u30b5\u30fc\u30d0\u30fc\u3067\u306f32\u30d3\u30c3\u30c8\u306e\u5834\u5408\u3082\uff09\u306e\u9593\u3067\u52d5\u4f5c\u304c\u7570\u306a\u308a\u3001\u539f\u56e0\u7279\u5b9a\u304c\u96e3\u3057\u3044\u30d0\u30b0\u3092\u5f15\u304d\u8d77\u3053\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u89e3\u6c7a\u7b56:<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u74b0\u5883\u60c5\u5831\u3092\u65e9\u671f\u306b\u30c1\u30a7\u30c3\u30af\u3059\u308b:<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u8d77\u52d5\u6642\u306b\u78ba\u8a8d\nif (PHP_INT_SIZE &lt; 8) {\n    error_log('\u8b66\u544a: 32\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u5b9f\u884c\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u5927\u304d\u306a\u6574\u6570\u5024\u306e\u51e6\u7406\u306b\u6ce8\u610f\u3057\u3066\u304f\u3060\u3055\u3044\u3002');\n}\n<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u5927\u304d\u306a\u6570\u5024\u306f\u6587\u5b57\u5217\u3068\u3057\u3066\u51e6\u7406\u3059\u308b:<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5927\u304d\u306a\u6570\u5024\u306f\u6587\u5b57\u5217\u306e\u307e\u307e\u51e6\u7406\n$large_id = \"2500000000\";\n\n\/\/ \u6587\u5b57\u5217\u306e\u307e\u307e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30d1\u30e9\u30e1\u30fc\u30bf\u3068\u3057\u3066\u4f7f\u7528\n$stmt = $pdo-&gt;prepare(\"SELECT * FROM large_table WHERE id = ?\");\n$stmt-&gt;execute([$large_id]); \/\/ \u6587\u5b57\u5217\u306e\u307e\u307e\u6e21\u3059\n<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>BCMath\u62e1\u5f35\u3092\u4f7f\u7528\u3059\u308b:<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u74b0\u5883\u306b\u4f9d\u5b58\u3057\u306a\u3044\u8a08\u7b97\nif (extension_loaded('bcmath')) {\n    $a = \"2147483648\";\n    $b = \"1000000000\";\n    $sum = bcadd($a, $b); \/\/ \"3147483648\"\n    \n    \/\/ \u6bd4\u8f03\u3082\u53ef\u80fd\n    if (bccomp($sum, \"3000000000\") &gt; 0) {\n        echo \"\u5408\u8a08\u306f30\u5104\u3088\u308a\u5927\u304d\u3044\";\n    }\n}\n<\/pre>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\">\n<li><strong>\u5909\u63db\u524d\u306b\u7bc4\u56f2\u30c1\u30a7\u30c3\u30af\u3059\u308b:<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">function safeIntval($value) {\n    \/\/ \u6587\u5b57\u5217\u3067\u6bd4\u8f03\n    if (is_string($value) &amp;&amp; bccomp($value, PHP_INT_MAX) &gt; 0) {\n        \/\/ \u6574\u6570\u7bc4\u56f2\u3092\u8d85\u3048\u308b\u5834\u5408\u306e\u51e6\u7406\n        return PHP_INT_MAX; \/\/ \u307e\u305f\u306f\u4f8b\u5916\u3092\u30b9\u30ed\u30fc\n    }\n    return intval($value);\n}\n\n$id = safeIntval(\"2500000000\");\n<\/pre>\n\n\n\n<p>32\u30d3\u30c3\u30c8\u306864\u30d3\u30c3\u30c8\u306e\u4e92\u63db\u6027\u554f\u984c\u306f\u3001\u7279\u306b\u5927\u898f\u6a21\u306a\u30c7\u30fc\u30bf\u3092\u6271\u3046\u30b7\u30b9\u30c6\u30e0\u3084ID\u5024\u304c\u5897\u5927\u3057\u7d9a\u3051\u308b\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u767a\u751f\u3057\u3084\u3059\u304f\u306a\u308a\u307e\u3059\u3002\u30af\u30e9\u30a6\u30c9\u30b5\u30fc\u30d3\u30b9\u3078\u306e\u79fb\u884c\u3084\u30b3\u30f3\u30c6\u30ca\u6280\u8853\u306e\u666e\u53ca\u306b\u3088\u308a\u74b0\u5883\u304c\u6df7\u5728\u3059\u308b\u3053\u3068\u3082\u591a\u304f\u306a\u308b\u305f\u3081\u3001\u3053\u306e\u554f\u984c\u306b\u5bfe\u3059\u308b\u610f\u8b58\u3092\u9ad8\u3081\u3066\u304a\u304f\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-29\">\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3092\u9632\u3050\u305f\u3081\u306e\u5bfe\u7b56\u3068\u4ee3\u66ff\u30a2\u30d7\u30ed\u30fc\u30c1<\/h3>\n\n\n\n<p>\u6574\u6570\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306f\u3001\u5024\u304cPHP\u306e\u6574\u6570\u578b\u306e\u4e0a\u9650\u3092\u8d85\u3048\u305f\u3068\u304d\u306b\u767a\u751f\u3059\u308b\u554f\u984c\u3067\u3059\u3002\u7279\u306b<code>intval()<\/code>\u95a2\u6570\u306f\u3001\u5927\u304d\u306a\u6570\u5024\u3092\u5909\u63db\u3059\u308b\u969b\u306b\u4e0a\u9650\u5024\u3067\u9759\u304b\u306b\u5207\u308a\u8a70\u3081\u3066\u3057\u307e\u3046\u305f\u3081\u3001\u6c17\u3065\u304d\u306b\u304f\u3044\u30d0\u30b0\u306e\u539f\u56e0\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306e\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ 64\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306e\u6574\u6570\u4e0a\u9650\u3092\u8d85\u3048\u308b\u5024\n$very_large = \"9223372036854775808\"; \/\/ PHP_INT_MAX + 1\necho intval($very_large); \/\/ 9223372036854775807\uff08\u6700\u5927\u5024\u306b\u5207\u308a\u8a70\u3081\u3089\u308c\u308b\uff09\n\n\/\/ \u8a08\u7b97\u7d50\u679c\u306e\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\n$max = PHP_INT_MAX;\n$result = $max + 1;\necho intval($result); \/\/ PHP 7\u4ee5\u964d\u306f\u6d6e\u52d5\u5c0f\u6570\u70b9\u306b\u5909\u63db\u5f8c\u3001\u6574\u6570\u306b\u623b\u3059\u306e\u3067\u6700\u5927\u5024\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306a\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306f\u3001\u7d71\u8a08\u51e6\u7406\u3084\u5927\u304d\u306aID\u3092\u6271\u3046\u30b7\u30b9\u30c6\u30e0\u3067\u554f\u984c\u3092\u5f15\u304d\u8d77\u3053\u3059\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u3067\u306f\u3001\u3053\u308c\u3092\u9632\u3050\u305f\u3081\u306e\u5bfe\u7b56\u3092\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<p><strong>1. BCMath\u62e1\u5f35\u3092\u4f7f\u7528\u3057\u305f\u4efb\u610f\u7cbe\u5ea6\u8a08\u7b97<\/strong><\/p>\n\n\n\n<p>BCMath\u62e1\u5f35\u3092\u4f7f\u7528\u3059\u308b\u3068\u3001PHP\u306e\u6574\u6570\u578b\u306e\u5236\u9650\u3092\u8d85\u3048\u308b\u5927\u304d\u306a\u6570\u5024\u3092\u6587\u5b57\u5217\u3068\u3057\u3066\u6271\u3046\u3053\u3068\u304c\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ BCMath\u3092\u4f7f\u3063\u305f\u5b89\u5168\u306a\u8a08\u7b97\n$large1 = \"9223372036854775807\"; \/\/ PHP_INT_MAX\n$large2 = \"1\";\n$sum = bcadd($large1, $large2); \/\/ \"9223372036854775808\"\n\n\/\/ \u6574\u6570\u7bc4\u56f2\u3092\u30c1\u30a7\u30c3\u30af\u3057\u3066\u304b\u3089\u5909\u63db\nfunction safeIntval($value) {\n    \/\/ \u5024\u304c\u6574\u6570\u7bc4\u56f2\u5185\u304b\u30c1\u30a7\u30c3\u30af\n    if (bccomp($value, PHP_INT_MAX) &gt; 0) {\n        \/\/ \u4e0a\u9650\u3092\u8d85\u3048\u308b\u5834\u5408\u306e\u51e6\u7406\u65b9\u6cd5\u3092\u9078\u629e\n        return PHP_INT_MAX; \/\/ \u307e\u305f\u306f\u4f8b\u5916\u3092\u30b9\u30ed\u30fc\n    }\n    return intval($value);\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$id = safeIntval(\"9223372036854775808\"); \/\/ PHP_INT_MAX\n<\/pre>\n\n\n\n<p><strong>2. \u6587\u5b57\u5217\u3068\u3057\u3066\u6271\u3046\u65b9\u6cd5<\/strong><\/p>\n\n\n\n<p>\u7279\u306b\u5927\u304d\u306aID\u3084\u8b58\u5225\u5b50\u3092\u6271\u3046\u5834\u5408\u306f\u3001\u6700\u521d\u304b\u3089\u6700\u5f8c\u307e\u3067\u6587\u5b57\u5217\u3068\u3057\u3066\u51e6\u7406\u3059\u308b\u3053\u3068\u3067\u554f\u984c\u3092\u56de\u907f\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ ID\u3092\u6587\u5b57\u5217\u3068\u3057\u3066\u6271\u3046\n$record_id = \"12345678901234567890\"; \/\/ \u6574\u6570\u7bc4\u56f2\u3092\u8d85\u3048\u308b\u5927\u304d\u306aID\n\n\/\/ \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u3067\u3082\u6587\u5b57\u5217\u30d1\u30e9\u30e1\u30fc\u30bf\u3068\u3057\u3066\u4f7f\u7528\n$stmt = $pdo-&gt;prepare(\"SELECT * FROM large_records WHERE id = ?\");\n$stmt-&gt;execute([$record_id]); \/\/ \u6587\u5b57\u5217\u306e\u307e\u307e\u6e21\u3059\n\n\/\/ \u6bd4\u8f03\u3082\u6587\u5b57\u5217\u3068\u3057\u3066\u884c\u3046\nif ($record_id === \"12345678901234567890\") {\n    \/\/ \u51e6\u7406...\n}\n<\/pre>\n\n\n\n<p><strong>3. \u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306e\u691c\u51fa<\/strong><\/p>\n\n\n\n<p>\u6f14\u7b97\u7d50\u679c\u304c\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3059\u308b\u304b\u3069\u3046\u304b\u3092\u4e8b\u524d\u306b\u30c1\u30a7\u30c3\u30af\u3059\u308b\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u52a0\u7b97\u304c\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3059\u308b\u304b\u30c1\u30a7\u30c3\u30af\u3059\u308b\u95a2\u6570\nfunction willAddOverflow($a, $b) {\n    if ($b &gt; 0 &amp;&amp; $a &gt; PHP_INT_MAX - $b) return true;\n    if ($b &lt; 0 &amp;&amp; $a &lt; PHP_INT_MIN - $b) return true;\n    return false;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$a = PHP_INT_MAX - 5;\n$b = 10;\n\nif (willAddOverflow($a, $b)) {\n    \/\/ \u4ee3\u66ff\u30a2\u30d7\u30ed\u30fc\u30c1\u3092\u4f7f\u7528\n    $result = bcadd((string)$a, (string)$b);\n} else {\n    \/\/ \u901a\u5e38\u306e\u52a0\u7b97\u3067\u5b89\u5168\n    $result = $a + $b;\n}\n<\/pre>\n\n\n\n<p><strong>4. \u6c4e\u7528\u7684\u306aBigInteger\u5b9f\u88c5<\/strong><\/p>\n\n\n\n<p>\u5927\u304d\u306a\u6574\u6570\u3092\u6271\u3046\u305f\u3081\u306e\u5c02\u7528\u30af\u30e9\u30b9\u3092\u4f5c\u6210\u3059\u308b\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class BigInteger {\n    private $value;\n    \n    public function __construct($value) {\n        $this-&gt;value = (string)$value;\n    }\n    \n    public function add($other) {\n        return new BigInteger(bcadd($this-&gt;value, (string)$other));\n    }\n    \n    public function multiply($other) {\n        return new BigInteger(bcmul($this-&gt;value, (string)$other));\n    }\n    \n    \/\/ \u5b89\u5168\u306bint\u306b\u5909\u63db\uff08\u7bc4\u56f2\u5185\u306e\u5834\u5408\u306e\u307f\uff09\n    public function toIntIfPossible() {\n        if (bccomp($this-&gt;value, PHP_INT_MAX) &gt; 0) {\n            throw new OverflowException(\"\u5024\u304c\u5927\u304d\u3059\u304e\u3066PHP\u6574\u6570\u578b\u306b\u5909\u63db\u3067\u304d\u307e\u305b\u3093\");\n        }\n        return intval($this-&gt;value);\n    }\n    \n    public function __toString() {\n        return $this-&gt;value;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$largeNumber = new BigInteger(\"12345678901234567890\");\n$result = $largeNumber-&gt;multiply(2);\necho $result; \/\/ \"24691357802469135780\"\n<\/pre>\n\n\n\n<p><strong>5. \u5206\u5272\u8a08\u7b97\u30c6\u30af\u30cb\u30c3\u30af<\/strong><\/p>\n\n\n\n<p>\u975e\u5e38\u306b\u5927\u304d\u306a\u8a08\u7b97\u3092\u8907\u6570\u306e\u30b9\u30c6\u30c3\u30d7\u306b\u5206\u5272\u3059\u308b\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5927\u91cf\u306e\u30c7\u30fc\u30bf\u306e\u5408\u8a08\u3092\u5b89\u5168\u306b\u8a08\u7b97\nfunction safeSumLargeDataset($numbers) {\n    \/\/ \u90e8\u5206\u5408\u8a08\u3092\u8a08\u7b97\n    $subtotals = [];\n    $current_sum = 0;\n    $count = 0;\n    \n    foreach ($numbers as $num) {\n        \/\/ \u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306e\u53ef\u80fd\u6027\u3092\u30c1\u30a7\u30c3\u30af\n        if ($current_sum &gt; PHP_INT_MAX - $num) {\n            \/\/ \u90e8\u5206\u5408\u8a08\u3092\u4fdd\u5b58\u3057\u3066\u65b0\u3057\u3044\u96c6\u8a08\u3092\u958b\u59cb\n            $subtotals[] = (string)$current_sum;\n            $current_sum = $num;\n        } else {\n            $current_sum += $num;\n        }\n        $count++;\n    }\n    \n    \/\/ \u6700\u5f8c\u306e\u90e8\u5206\u5408\u8a08\u3092\u8ffd\u52a0\n    if ($current_sum &gt; 0) {\n        $subtotals[] = (string)$current_sum;\n    }\n    \n    \/\/ BCMath\u3067\u90e8\u5206\u5408\u8a08\u3092\u5408\u7b97\n    $total = \"0\";\n    foreach ($subtotals as $subtotal) {\n        $total = bcadd($total, $subtotal);\n    }\n    \n    return $total;\n}\n<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u624b\u6cd5\u3092\u72b6\u6cc1\u306b\u5fdc\u3058\u3066\u4f7f\u3044\u5206\u3051\u308b\u3053\u3068\u3067\u3001\u6574\u6570\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306b\u3088\u308b\u554f\u984c\u3092\u52b9\u679c\u7684\u306b\u9632\u6b62\u3067\u304d\u307e\u3059\u3002\u7279\u306b\u91d1\u878d\u30c7\u30fc\u30bf\u3084\u7d71\u8a08\u60c5\u5831\u306a\u3069\u3001\u6b63\u78ba\u3055\u304c\u91cd\u8981\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306f\u3001<code>intval()<\/code>\u306e\u9650\u754c\u3092\u8a8d\u8b58\u3057\u3001\u9069\u5207\u306a\u4ee3\u66ff\u624b\u6bb5\u3092\u9078\u629e\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-30\">NULL\u3084\u7a7a\u6587\u5b57\u5217\u306b\u5bfe\u3059\u308b\u4e88\u671f\u305b\u306c\u5909\u63db\u7d50\u679c\u3078\u306e\u5bfe\u51e6\u6cd5<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u969b\u306b\u898b\u843d\u3068\u3057\u304c\u3061\u306a\u843d\u3068\u3057\u7a74\u306e\u4e00\u3064\u304c\u3001NULL\u5024\u3084\u7a7a\u6587\u5b57\u5217\u306e\u6271\u3044\u3067\u3059\u3002\u3053\u308c\u3089\u306e\u5024\u306f\u5168\u3066\u540c\u3058\u7d50\u679c\u306b\u306a\u3063\u3066\u3057\u307e\u3046\u305f\u3081\u3001\u610f\u56f3\u3057\u306a\u3044\u52d5\u4f5c\u3092\u5f15\u304d\u8d77\u3053\u3059\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u554f\u984c\u3068\u306a\u308b\u6319\u52d5:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">echo intval(null);      \/\/ \u7d50\u679c: 0\necho intval(\"\");        \/\/ \u7d50\u679c: 0\necho intval(\"0\");       \/\/ \u7d50\u679c: 0\necho intval(false);     \/\/ \u7d50\u679c: 0\n<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5024\u304c\u3059\u3079\u3066\u540c\u3058\u7d50\u679c\uff080\uff09\u306b\u306a\u308b\u3053\u3068\u3067\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u554f\u984c\u304c\u751f\u3058\u307e\u3059\uff1a<\/p>\n\n\n\n<p><strong>1. \u672a\u5165\u529b\u3068\u660e\u793a\u7684\u306a\u30bc\u30ed\u5165\u529b\u306e\u533a\u5225\u304c\u3067\u304d\u306a\u3044<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30d5\u30a9\u30fc\u30e0\u304b\u3089\u306e\u5165\u529b\u51e6\u7406\n$quantity = $_POST['quantity'] ?? null;\n$quantity_int = intval($quantity); \/\/ \u5e38\u306b0\u306b\u306a\u308b\n\nif ($quantity_int === 0) {\n    \/\/ \u6570\u91cf\u304c\u6307\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u306e\u304b\u3001\n    \/\/ \u660e\u793a\u7684\u306b0\u304c\u5165\u529b\u3055\u308c\u305f\u306e\u304b\u533a\u5225\u3067\u304d\u306a\u3044\n}\n<\/pre>\n\n\n\n<p><strong>2. \u6761\u4ef6\u5206\u5c90\u3067\u306e\u8aa4\u5224\u5b9a<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ URL\u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u30c1\u30a7\u30c3\u30af\n$user_id = intval($_GET['user_id'] ?? null);\n\nif ($user_id === 0) {\n    \/\/ \u30d1\u30e9\u30e1\u30fc\u30bf\u304c\u306a\u3044\u5834\u5408\u3082\u3001\u30d1\u30e9\u30e1\u30fc\u30bf\u304c\u7a7a\u306e\u5834\u5408\u3082\u3001\n    \/\/ \u660e\u793a\u7684\u306b \"0\" \u304c\u6307\u5b9a\u3055\u308c\u305f\u5834\u5408\u3082\u3001\u3059\u3079\u3066\u3053\u3053\u306b\u5165\u308b\n    echo \"\u7121\u52b9\u306a\u30e6\u30fc\u30b6\u30fcID\u3067\u3059\";\n}\n<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u554f\u984c\u3092\u89e3\u6c7a\u3059\u308b\u305f\u3081\u306e\u52b9\u679c\u7684\u306a\u5bfe\u51e6\u6cd5\u3092\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<p><strong>\u5bfe\u51e6\u6cd51: \u5909\u63db\u524d\u306b\u5b58\u5728\u30c1\u30a7\u30c3\u30af\u3092\u884c\u3046<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u3088\u308a\u5b89\u5168\u306aintval\u95a2\u6570\nfunction safeIntval($value, $default = null) {\n    \/\/ null\u3084\u7a7a\u6587\u5b57\u306e\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u8fd4\u3059\n    if ($value === null || $value === '') {\n        return $default;\n    }\n    return intval($value);\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$id = safeIntval($_GET['id'] ?? null, null);\n\nif ($id === null) {\n    echo \"ID\u304c\u6307\u5b9a\u3055\u308c\u3066\u3044\u307e\u305b\u3093\";\n} else if ($id === 0) {\n    echo \"ID\u304c\u30bc\u30ed\u3067\u3059\";\n} else {\n    echo \"ID\u306f $id \u3067\u3059\";\n}\n<\/pre>\n\n\n\n<p><strong>\u5bfe\u51e6\u6cd52: \u578b\u3068\u5024\u3092\u660e\u793a\u7684\u306b\u691c\u8a3c\u3059\u308b<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u8a73\u7d30\u306a\u691c\u8a3c\nif (!isset($_GET['id'])) {\n    \/\/ \u30d1\u30e9\u30e1\u30fc\u30bf\u304c\u5b58\u5728\u3057\u306a\u3044\n    echo \"ID\u30d1\u30e9\u30e1\u30fc\u30bf\u304c\u5fc5\u8981\u3067\u3059\";\n} else if ($_GET['id'] === '') {\n    \/\/ \u30d1\u30e9\u30e1\u30fc\u30bf\u306f\u5b58\u5728\u3059\u308b\u304c\u7a7a\n    echo \"ID\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\";\n} else if (!is_numeric($_GET['id'])) {\n    \/\/ \u6570\u5024\u3068\u3057\u3066\u89e3\u91c8\u3067\u304d\u306a\u3044\n    echo \"ID\u306f\u6570\u5024\u3067\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\";\n} else {\n    \/\/ \u3053\u3053\u3067\u5b89\u5168\u306b\u5909\u63db\u3067\u304d\u308b\n    $id = intval($_GET['id']);\n    \/\/ \u51e6\u7406\u3092\u7d99\u7d9a...\n}\n<\/pre>\n\n\n\n<p><strong>\u5bfe\u51e6\u6cd53: \u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u3068\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u306e\u7d44\u307f\u5408\u308f\u305b<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5305\u62ec\u7684\u306a\u30d1\u30e9\u30e1\u30fc\u30bf\u53d6\u5f97\u95a2\u6570\nfunction getIntParameter($name, $options = []) {\n    $input = $_REQUEST[$name] ?? null;\n    \n    \/\/ \u5b58\u5728\u30c1\u30a7\u30c3\u30af\n    if ($input === null) {\n        return $options['default'] ?? null;\n    }\n    \n    \/\/ \u7a7a\u6587\u5b57\u30c1\u30a7\u30c3\u30af\n    if ($input === '') {\n        return $options['empty_value'] ?? $options['default'] ?? null;\n    }\n    \n    \/\/ \u6570\u5024\u30c1\u30a7\u30c3\u30af\n    if (!is_numeric($input)) {\n        return $options['invalid_value'] ?? $options['default'] ?? null;\n    }\n    \n    \/\/ \u6574\u6570\u5909\u63db\n    $value = intval($input);\n    \n    \/\/ \u7bc4\u56f2\u30c1\u30a7\u30c3\u30af\uff08\u30aa\u30d7\u30b7\u30e7\u30f3\uff09\n    if (isset($options['min']) &amp;&amp; $value &lt; $options['min']) {\n        return $options['min'];\n    }\n    \n    if (isset($options['max']) &amp;&amp; $value &gt; $options['max']) {\n        return $options['max'];\n    }\n    \n    return $value;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$page = getIntParameter('page', [\n    'default' =&gt; 1,\n    'min' =&gt; 1,\n    'empty_value' =&gt; 1\n]);\n<\/pre>\n\n\n\n<p><strong>\u5bfe\u51e6\u6cd54: Nullable\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u30a2\u30d7\u30ed\u30fc\u30c1\uff08PHP 7.1\u4ee5\u964d\uff09<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class OptionalInt {\n    private $value;\n    private $isPresent;\n    \n    public static function of($input) {\n        if ($input === null || $input === '') {\n            return new self(null, false);\n        }\n        return new self(intval($input), true);\n    }\n    \n    private function __construct($value, $isPresent) {\n        $this-&gt;value = $value;\n        $this-&gt;isPresent = $isPresent;\n    }\n    \n    public function isPresent() {\n        return $this-&gt;isPresent;\n    }\n    \n    public function getValue($default = null) {\n        return $this-&gt;isPresent ? $this-&gt;value : $default;\n    }\n    \n    public function isZero() {\n        return $this-&gt;isPresent &amp;&amp; $this-&gt;value === 0;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$quantity = OptionalInt::of($_POST['quantity'] ?? null);\n\nif (!$quantity-&gt;isPresent()) {\n    echo \"\u6570\u91cf\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\";\n} else if ($quantity-&gt;isZero()) {\n    echo \"\u6570\u91cf\u306f0\u3088\u308a\u5927\u304d\u3044\u5024\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\";\n} else {\n    $value = $quantity-&gt;getValue();\n    echo \"\u9078\u629e\u3055\u308c\u305f\u6570\u91cf: $value\";\n}\n<\/pre>\n\n\n\n<p><strong>\u5b9f\u8df5\u7684\u306a\u30a2\u30c9\u30d0\u30a4\u30b9:<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u4e0d\u78ba\u304b\u306a\u5165\u529b\u306b\u306f\u5e38\u306b\u524d\u51e6\u7406\u3092\u884c\u3046<\/strong> \u2013 \u7279\u306b\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3084API\u30ea\u30af\u30a8\u30b9\u30c8\u306a\u3069<\/li>\n\n\n\n<li><strong>\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u5177\u4f53\u7684\u306b<\/strong> \u2013 \u300c\u5024\u304c\u3042\u308a\u307e\u305b\u3093\u300d\u3068\u300c\u30bc\u30ed\u306f\u7121\u52b9\u3067\u3059\u300d\u306f\u5225\u306e\u30a8\u30e9\u30fc\u3068\u3057\u3066\u6271\u3046<\/li>\n\n\n\n<li><strong>\u4e00\u8cab\u3057\u305f\u30a2\u30d7\u30ed\u30fc\u30c1\u3092\u63a1\u7528\u3059\u308b<\/strong> \u2013 \u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5168\u4f53\u3067\u540c\u3058\u30d1\u30bf\u30fc\u30f3\u3092\u4f7f\u7528\u3059\u308b<\/li>\n\n\n\n<li><strong>\u65e9\u671f\u306b\u578b\u3092\u78ba\u5b9a\u3059\u308b<\/strong> \u2013 \u3067\u304d\u308b\u3060\u3051\u5165\u53e3\u306b\u8fd1\u3044\u5834\u6240\u3067\u9069\u5207\u306a\u578b\u306b\u5909\u63db\u3059\u308b<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5bfe\u51e6\u6cd5\u3092\u72b6\u6cc1\u306b\u5fdc\u3058\u3066\u9069\u7528\u3059\u308b\u3053\u3068\u3067\u3001NULL\u5024\u3084\u7a7a\u6587\u5b57\u5217\u306b\u95a2\u9023\u3059\u308b\u4e88\u671f\u305b\u306c\u52d5\u4f5c\u3092\u9632\u304e\u3001\u3088\u308a\u5805\u7262\u306a\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-31\">\u56fd\u969b\u5316\u5bfe\u5fdc\u6642\u306e\u6570\u5024\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306b\u3088\u308b\u554f\u984c\u3068\u89e3\u6c7a\u7b56<\/h3>\n\n\n\n<p>\u30b0\u30ed\u30fc\u30d0\u30eb\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u958b\u767a\u3059\u308b\u969b\u306b\u898b\u843d\u3068\u3055\u308c\u304c\u3061\u306a\u554f\u984c\u306e\u4e00\u3064\u304c\u3001\u56fd\u3084\u5730\u57df\u306b\u3088\u3063\u3066\u7570\u306a\u308b\u6570\u5024\u306e\u8868\u8a18\u6cd5\u3067\u3059\u3002<code>intval()<\/code>\u95a2\u6570\u306f\u56fd\u969b\u7684\u306a\u6570\u5024\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u3092\u8003\u616e\u305b\u305a\u3001\u5e38\u306b\u82f1\u8a9e\uff08US\uff09\u5f62\u5f0f\u3092\u524d\u63d0\u3068\u3057\u3066\u3044\u308b\u305f\u3081\u3001\u4e88\u671f\u305b\u306c\u5909\u63db\u7d50\u679c\u3092\u5f15\u304d\u8d77\u3053\u3059\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u56fd\u969b\u7684\u306a\u6570\u5024\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306e\u9055\u3044:<\/strong><\/p>\n\n\n<div id=\"id-3796c17c-0c1a-40e1-ac4e-bfe305f78188\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u5730\u57df<\/th><th>\u5343\u306e\u4f4d\u533a\u5207\u308a<\/th><th>\u5c0f\u6570\u70b9<\/th><th>\u8868\u8a18\u4f8b (1234.56)<\/th><\/tr><\/thead><tbody><tr><td>\u7c73\u56fd\/\u65e5\u672c<\/td><td>\u30ab\u30f3\u30de (,)<\/td><td>\u30d4\u30ea\u30aa\u30c9 (.)<\/td><td>1,234.56<\/td><\/tr><tr><td>\u30c9\u30a4\u30c4\/\u30d5\u30e9\u30f3\u30b9<\/td><td>\u30d4\u30ea\u30aa\u30c9 (.)<\/td><td>\u30ab\u30f3\u30de (,)<\/td><td>1.234,56<\/td><\/tr><tr><td>\u5317\u6b27<\/td><td>\u30b9\u30da\u30fc\u30b9<\/td><td>\u30ab\u30f3\u30de (,)<\/td><td>1 234,56<\/td><\/tr><tr><td>\u30a4\u30f3\u30c9<\/td><td>\u72ec\u81ea\u5f62\u5f0f<\/td><td>\u30d4\u30ea\u30aa\u30c9 (.)<\/td><td>1,23,456.78<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p><strong>intval()\u95a2\u6570\u306e\u554f\u984c\u70b9:<\/strong><\/p>\n\n\n\n<p><code>intval()<\/code>\u306f\u3001\u3053\u308c\u3089\u306e\u56fd\u969b\u7684\u306a\u6570\u5024\u8868\u8a18\u3092\u9069\u5207\u306b\u89e3\u91c8\u3067\u304d\u307e\u305b\u3093\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u69d8\u3005\u306a\u8868\u8a18\u306b\u5bfe\u3059\u308bintval()\u306e\u6319\u52d5\necho intval(\"1,234.56\");  \/\/ \u7d50\u679c: 1\uff08\u30ab\u30f3\u30de\u4ee5\u964d\u306f\u7121\u8996\uff09\necho intval(\"1.234,56\");  \/\/ \u7d50\u679c: 1\uff08\u30d4\u30ea\u30aa\u30c9\u4ee5\u964d\u306f\u7121\u8996\uff09\necho intval(\"1 234,56\");  \/\/ \u7d50\u679c: 1\uff08\u30b9\u30da\u30fc\u30b9\u4ee5\u964d\u306f\u7121\u8996\uff09\n<\/pre>\n\n\n\n<p>\u3053\u308c\u306b\u3088\u308a\u3001\u4f8b\u3048\u3070\u30c9\u30a4\u30c4\u306e\u30e6\u30fc\u30b6\u30fc\u304c\u5165\u529b\u3057\u305f \u201c1.234\u201d\uff08\u5b9f\u969b\u306b\u306f1,234\u3092\u610f\u5473\u3059\u308b\uff09\u304c1\u3068\u3057\u3066\u89e3\u91c8\u3055\u308c\u308b\u3068\u3044\u3063\u305f\u554f\u984c\u304c\u767a\u751f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u89e3\u6c7a\u7b561: PHP intl\u62e1\u5f35\u3092\u4f7f\u7528\u3059\u308b<\/strong><\/p>\n\n\n\n<p>\u6700\u3082\u5805\u7262\u306a\u89e3\u6c7a\u7b56\u306f\u3001PHP intl\u62e1\u5f35\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u56fd\u969b\u5316\u5bfe\u5fdc\u306e\u6574\u6570\u5909\u63db\n * @param string $value \u5909\u63db\u3059\u308b\u6570\u5024\u6587\u5b57\u5217\n * @param string $locale \u30ed\u30b1\u30fc\u30eb\u8b58\u5225\u5b50\n * @return int \u5909\u63db\u3055\u308c\u305f\u6574\u6570\n *\/\nfunction intlIntval($value, $locale = 'en_US') {\n    if (!extension_loaded('intl')) {\n        \/\/ intl\u62e1\u5f35\u304c\u306a\u3044\u5834\u5408\u306f\u4ee3\u66ff\u51e6\u7406\n        return fallbackIntval($value, $locale);\n    }\n    \n    if ($value === null || $value === '') {\n        return 0;\n    }\n    \n    try {\n        $formatter = new NumberFormatter($locale, NumberFormatter::DECIMAL);\n        $parsed = $formatter-&gt;parse($value);\n        \n        if ($parsed === false) {\n            return 0;\n        }\n        \n        return intval($parsed);\n    } catch (Exception $e) {\n        \/\/ \u89e3\u6790\u30a8\u30e9\u30fc\u6642\u306f0\u3092\u8fd4\u3059\n        return 0;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$german_number = \"1.234,56\";\necho intlIntval($german_number, 'de_DE'); \/\/ \u7d50\u679c: 1234\n<\/pre>\n\n\n\n<p><strong>\u89e3\u6c7a\u7b562: \u30ab\u30b9\u30bf\u30e0\u5909\u63db\u95a2\u6570\uff08intl\u62e1\u5f35\u306a\u3057\uff09<\/strong><\/p>\n\n\n\n<p>intl\u62e1\u5f35\u304c\u5229\u7528\u3067\u304d\u306a\u3044\u5834\u5408\u306e\u305f\u3081\u306e\u4ee3\u66ff\u30a2\u30d7\u30ed\u30fc\u30c1\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30ed\u30b1\u30fc\u30eb\u306b\u57fa\u3065\u3044\u3066\u6570\u5024\u6587\u5b57\u5217\u3092\u6a19\u6e96\u5f62\u5f0f\u306b\u5909\u63db\n *\/\nfunction normalizeNumberByLocale($number, $locale = 'en_US') {\n    \/\/ \u6570\u5024\u4ee5\u5916\u3092\u9664\u53bb\uff08\u7a7a\u767d\u3001\u901a\u8ca8\u8a18\u53f7\u306a\u3069\uff09\n    $number = trim($number);\n    \n    switch ($locale) {\n        case 'de_DE':\n        case 'fr_FR':\n        case 'es_ES':\n        case 'it_IT':\n            \/\/ \u6b27\u5dde\u5f62\u5f0f (1.234,56) \u2192 \u6a19\u6e96\u5f62\u5f0f (1234.56)\n            $number = str_replace(' ', '', $number); \/\/ \u30b9\u30da\u30fc\u30b9\u524a\u9664\n            $number = str_replace('.', '', $number); \/\/ \u5343\u306e\u4f4d\u533a\u5207\u308a\u524a\u9664\n            $number = str_replace(',', '.', $number); \/\/ \u5c0f\u6570\u70b9\u3092\u6a19\u6e96\u5f62\u5f0f\u306b\u5909\u63db\n            break;\n            \n        case 'en_US':\n        case 'ja_JP':\n        case 'ko_KR':\n        default:\n            \/\/ \u82f1\u8a9e\/\u30a2\u30b8\u30a2\u5f62\u5f0f (1,234.56)\n            $number = str_replace(',', '', $number); \/\/ \u5343\u306e\u4f4d\u533a\u5207\u308a\u524a\u9664\n            break;\n    }\n    \n    return $number;\n}\n\n\/\/ \u6574\u6570\u5909\u63db\u95a2\u6570\nfunction localeIntval($value, $locale = 'en_US') {\n    if ($value === null || $value === '') {\n        return 0;\n    }\n    \n    $normalized = normalizeNumberByLocale($value, $locale);\n    return intval($normalized);\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$french_number = \"1 234,56\";\necho localeIntval($french_number, 'fr_FR'); \/\/ \u7d50\u679c: 1234\n<\/pre>\n\n\n\n<p><strong>\u5b9f\u88c5\u306e\u305f\u3081\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9:<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e6\u30fc\u30b6\u30fc\u306e\u30ed\u30b1\u30fc\u30eb\u3092\u5e38\u306b\u628a\u63e1\u3059\u308b:<\/strong> <code>\/\/ \u30e6\u30fc\u30b6\u30fc\u8a2d\u5b9a\u3001\u30bb\u30c3\u30b7\u30e7\u30f3\u3001\u307e\u305f\u306f\u30d6\u30e9\u30a6\u30b6\u304b\u3089\u53d6\u5f97 $locale = $_SESSION['user_locale'] ?? 'en_US';<\/code><\/li>\n\n\n\n<li><strong>\u5165\u529b\u30d5\u30a9\u30fc\u30e0\u306b\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306e\u30d2\u30f3\u30c8\u3092\u8868\u793a\u3059\u308b:<\/strong> <code>&lt;label for=\"amount\"&gt;\u91d1\u984d\uff08\u4f8b: 1.234,56\uff09:&lt;\/label&gt; &lt;input type=\"text\" name=\"amount\" id=\"amount\"&gt;<\/code><\/li>\n\n\n\n<li><strong>\u53ef\u80fd\u3067\u3042\u308c\u3070HTML5\u306e\u6570\u5024\u5165\u529b\u3092\u4f7f\u7528\u3059\u308b:<\/strong> <code>&lt;input type=\"number\" step=\"0.01\" name=\"amount\"&gt;<\/code><\/li>\n\n\n\n<li><strong>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u306f\u6a19\u6e96\u5f62\u5f0f\u3067\u4fdd\u5b58\u3059\u308b:<\/strong> <code>\/\/ \u8868\u793a\u6642\u306f\u30ed\u30b1\u30fc\u30eb\u306b\u5408\u308f\u305b\u3001\u4fdd\u5b58\u6642\u306f\u6a19\u6e96\u5f62\u5f0f\u306b $amount_for_db = normalizeNumberByLocale($input_amount, $locale);<\/code><\/li>\n\n\n\n<li><strong>\u4e00\u8cab\u3057\u305f\u30a2\u30d7\u30ed\u30fc\u30c1\u3092\u63a1\u7528\u3059\u308b:<\/strong> \u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5168\u4f53\u3067\u540c\u3058\u56fd\u969b\u5316\u6226\u7565\u3092\u4f7f\u7528\u3057\u3001\u6df7\u4e71\u3092\u907f\u3051\u308b<\/li>\n<\/ol>\n\n\n\n<p>\u56fd\u969b\u5316\u5bfe\u5fdc\u306f\u4e00\u898b\u3059\u308b\u3068\u5c0f\u3055\u306a\u554f\u984c\u306b\u601d\u3048\u307e\u3059\u304c\u3001\u7279\u306b\u91d1\u878d\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3084\u7cbe\u5ea6\u304c\u91cd\u8981\u306a\u30b7\u30b9\u30c6\u30e0\u3067\u306f\u3001\u6b63\u78ba\u306a\u6570\u5024\u5909\u63db\u304c\u4e0d\u53ef\u6b20\u3067\u3059\u3002<code>intval()<\/code>\u95a2\u6570\u3092\u76f4\u63a5\u4f7f\u7528\u3059\u308b\u306e\u3067\u306f\u306a\u304f\u3001\u3053\u3053\u3067\u7d39\u4ecb\u3057\u305f\u3088\u3046\u306a\u56fd\u969b\u5316\u5bfe\u5fdc\u306e\u65b9\u6cd5\u3092\u63a1\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u4e16\u754c\u4e2d\u306e\u30e6\u30fc\u30b6\u30fc\u306b\u5bfe\u3057\u3066\u4fe1\u983c\u6027\u306e\u9ad8\u3044\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u63d0\u4f9b\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-32\">\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u4e0d\u8db3\u306b\u3088\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30db\u30fc\u30eb\u306e\u9632\u6b62\u65b9\u6cd5<\/h3>\n\n\n\n<p><code>intval()<\/code>\u95a2\u6570\u306f\u3001\u6574\u6570\u578b\u3078\u306e\u5909\u63db\u306b\u3088\u308a\u57fa\u672c\u7684\u306aSQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306a\u3069\u306e\u653b\u6483\u3092\u9632\u3050\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u304c\u3001\u3053\u308c\u3060\u3051\u3067\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3092\u78ba\u4fdd\u3059\u308b\u306b\u306f\u4e0d\u5341\u5206\u3067\u3059\u3002\u5358\u306a\u308b\u578b\u5909\u63db\u3060\u3051\u3067\u306f\u3001\u7bc4\u56f2\u30c1\u30a7\u30c3\u30af\u3084\u5024\u306e\u59a5\u5f53\u6027\u691c\u8a3c\u304c\u884c\u308f\u308c\u306a\u3044\u305f\u3081\u3001\u69d8\u3005\u306a\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\u3084\u4e0d\u5177\u5408\u304c\u6b8b\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u306a\u305cintval()\u3060\u3051\u3067\u306f\u4e0d\u5341\u5206\u306a\u306e\u304b\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u57fa\u672c\u7684\u306aSQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306f\u9632\u3052\u308b\n$id = intval($_GET['id']);\n$query = \"SELECT * FROM users WHERE id = $id\";\n\n\/\/ \u3057\u304b\u3057\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u554f\u984c\u306f\u6b8b\u308b\n\/\/ 1. \u8ca0\u6570\u3084\u7570\u5e38\u306b\u5927\u304d\u306a\u5024\u306e\u5165\u529b\n\/\/ 2. 0\u3084\u7279\u6b8a\u5024\u306e\u6271\u3044\n\/\/ 3. \u6a29\u9650\u30c1\u30a7\u30c3\u30af\u304c\u306a\u3044\n<\/pre>\n\n\n\n<p>\u5b9f\u969b\u306e\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u554f\u984c\u306e\u3042\u308b\u30b3\u30fc\u30c9\n$page = intval($_GET['page']);\n$items_per_page = intval($_GET['limit']);\n$offset = $page * $items_per_page;\n\n\/\/ \u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u30af\u30a8\u30ea\n$query = \"SELECT * FROM products LIMIT $items_per_page OFFSET $offset\";\n\n\/\/ \u6f5c\u5728\u7684\u306a\u554f\u984c\uff1a\n\/\/ - $page\u306b\u8ca0\u306e\u5024\u304c\u5165\u308b\u53ef\u80fd\u6027\n\/\/ - $items_per_page\u306b\u6975\u7aef\u306b\u5927\u304d\u306a\u5024\u304c\u5165\u308a\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u304c\u5897\u5927\n\/\/ - $offset\u304c\u5927\u304d\u3059\u304e\u3066\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u4f4e\u4e0b\n<\/pre>\n\n\n\n<p><strong>\u5b8c\u5168\u306a\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u306e\u305f\u3081\u306e\u30b9\u30c6\u30c3\u30d7\uff1a<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u578b\u30c1\u30a7\u30c3\u30af\u3068\u578b\u5909\u63db\u306e\u7d44\u307f\u5408\u308f\u305b<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">function validateInt($value, $options = []) {\n    \/\/ \u7a7a\u5024\u306e\u30c1\u30a7\u30c3\u30af\n    if ($value === null || $value === '') {\n        return $options['default'] ?? false;\n    }\n    \n    \/\/ \u6570\u5024\u5f62\u5f0f\u30c1\u30a7\u30c3\u30af\n    if (!is_numeric($value)) {\n        return false;\n    }\n    \n    \/\/ \u6574\u6570\u5909\u63db\n    $int_value = intval($value);\n    \n    \/\/ \u7bc4\u56f2\u30c1\u30a7\u30c3\u30af\n    if (isset($options['min']) &amp;&amp; $int_value &lt; $options['min']) {\n        return false;\n    }\n    \n    if (isset($options['max']) &amp;&amp; $int_value &gt; $options['max']) {\n        return false;\n    }\n    \n    return $int_value;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$page = validateInt($_GET['page'] ?? null, [\n    'default' =&gt; 1,\n    'min' =&gt; 1,\n    'max' =&gt; 100\n]);\n\nif ($page === false) {\n    \/\/ \u30a8\u30e9\u30fc\u51e6\u7406\n    $page = 1; \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u8a2d\u5b9a\n}\n<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u3068\u306e\u4f75\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<p>\u578b\u5909\u63db\u3060\u3051\u3067\u306a\u304f\u3001\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3055\u3089\u306b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u304c\u5411\u4e0a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u691c\u8a3c\u3068\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u306e\u7d44\u307f\u5408\u308f\u305b\n$id = validateInt($_GET['id'] ?? null, ['min' =&gt; 1]);\n\nif ($id === false) {\n    \/\/ \u30a8\u30e9\u30fc\u51e6\u7406\n    exit(\"Invalid ID\");\n}\n\n\/\/ PDO\u3067\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u3092\u4f7f\u7528\n$stmt = $pdo-&gt;prepare(\"SELECT * FROM users WHERE id = ?\");\n$stmt-&gt;execute([$id]);\n$user = $stmt-&gt;fetch(PDO::FETCH_ASSOC);\n<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30d3\u30b8\u30cd\u30b9\u30eb\u30fc\u30eb\u306b\u57fa\u3065\u304f\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3<\/strong><\/li>\n<\/ol>\n\n\n\n<p>\u4e00\u822c\u7684\u306a\u6570\u5024\u30c1\u30a7\u30c3\u30af\u3060\u3051\u3067\u306a\u304f\u3001\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u56fa\u6709\u306e\u30eb\u30fc\u30eb\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u3082\u91cd\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">function validateProductQuantity($qty) {\n    \/\/ \u57fa\u672c\u7684\u306a\u6574\u6570\u30c1\u30a7\u30c3\u30af\n    $qty = validateInt($qty, ['min' =&gt; 1]);\n    if ($qty === false) {\n        return false;\n    }\n    \n    \/\/ \u5728\u5eab\u30c1\u30a7\u30c3\u30af\uff08\u30d3\u30b8\u30cd\u30b9\u30ed\u30b8\u30c3\u30af\uff09\n    $product = getProduct($_POST['product_id']);\n    if ($qty &gt; $product['stock']) {\n        return false; \/\/ \u5728\u5eab\u4e0d\u8db3\n    }\n    \n    \/\/ \u6700\u5927\u6ce8\u6587\u6570\u30c1\u30a7\u30c3\u30af\uff08\u30d3\u30b8\u30cd\u30b9\u30ed\u30b8\u30c3\u30af\uff09\n    if ($qty &gt; 10 &amp;&amp; $product['restricted']) {\n        return false; \/\/ \u5236\u9650\u4ed8\u304d\u5546\u54c1\u306e\u6700\u5927\u6570\u91cf\n    }\n    \n    return $qty;\n}\n<\/pre>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\">\n<li><strong>\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u6a5f\u80fd\u306e\u6d3b\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<p>\u591a\u304f\u306e\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u306b\u306f\u5f37\u529b\u306a\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u6a5f\u80fd\u304c\u7d44\u307f\u8fbc\u307e\u308c\u3066\u3044\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ Laravel\u306e\u4f8b\npublic function store(Request $request)\n{\n    $validated = $request-&gt;validate([\n        'user_id' =&gt; 'required|integer|min:1|exists:users,id',\n        'product_id' =&gt; 'required|integer|min:1|exists:products,id',\n        'quantity' =&gt; 'required|integer|min:1|max:100',\n    ]);\n    \n    \/\/ \u691c\u8a3c\u6e08\u307f\u30c7\u30fc\u30bf\u3092\u5b89\u5168\u306b\u4f7f\u7528\n    Order::create($validated);\n}\n<\/pre>\n\n\n\n<p><strong>\u5b9f\u8df5\u7684\u306a\u7dcf\u5408\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u5bfe\u7b56\uff1a<\/strong><\/p>\n\n\n\n<p>\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3092\u78ba\u4fdd\u3059\u308b\u305f\u3081\u306b\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u7dcf\u5408\u7684\u306a\u30a2\u30d7\u30ed\u30fc\u30c1\u304c\u5fc5\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5165\u529b\u5024\u306e\u5fb9\u5e95\u7684\u306a\u691c\u8a3c\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u578b\u30c1\u30a7\u30c3\u30af\uff08is_numeric\u3001is_string\u306a\u3069\uff09<\/li>\n\n\n\n<li>\u7bc4\u56f2\u30c1\u30a7\u30c3\u30af\uff08\u6700\u5c0f\u5024\u30fb\u6700\u5927\u5024\uff09<\/li>\n\n\n\n<li>\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u30c1\u30a7\u30c3\u30af\uff08\u6b63\u898f\u8868\u73fe\u306a\u3069\uff09<\/li>\n\n\n\n<li>\u30d3\u30b8\u30cd\u30b9\u30eb\u30fc\u30eb\u306b\u57fa\u3065\u304f\u691c\u8a3c<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30a2\u30af\u30bb\u30b9\u306e\u4fdd\u8b77\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u306e\u4f7f\u7528<\/li>\n\n\n\n<li>PDO\u307e\u305f\u306fORM\u306e\u9069\u5207\u306a\u4f7f\u7528<\/li>\n\n\n\n<li>\u5165\u529b\u5024\u306e\u30a8\u30b9\u30b1\u30fc\u30d7\uff08SQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u5bfe\u7b56\uff09<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u305d\u306e\u4ed6\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u5bfe\u7b56\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>XSS\u5bfe\u7b56\uff08\u51fa\u529b\u30a8\u30b9\u30b1\u30fc\u30d7\uff09<\/li>\n\n\n\n<li>CSRF\u5bfe\u7b56\uff08\u30c8\u30fc\u30af\u30f3\u691c\u8a3c\uff09<\/li>\n\n\n\n<li>\u9069\u5207\u306a\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\uff08\u8a73\u7d30\u306a\u60c5\u5831\u6f0f\u6d29\u306e\u9632\u6b62\uff09<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<p>\u6700\u5f8c\u306b\u3001\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u306f\u7d99\u7d9a\u7684\u306a\u30d7\u30ed\u30bb\u30b9\u3067\u3042\u308b\u3053\u3068\u3092\u5fd8\u308c\u306a\u3044\u3067\u304f\u3060\u3055\u3044\u3002\u65b0\u3057\u3044\u8105\u5a01\u3084\u653b\u6483\u624b\u6cd5\u306b\u5bfe\u5fdc\u3059\u308b\u305f\u3081\u306b\u3001\u5b9a\u671f\u7684\u306b\u5bfe\u7b56\u3092\u898b\u76f4\u3057\u3001\u66f4\u65b0\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u307e\u305f\u3001\u4e00\u3064\u306e\u95a2\u6570\u3084\u624b\u6cd5\u306b\u4f9d\u5b58\u3059\u308b\u306e\u3067\u306f\u306a\u304f\u3001\u8907\u6570\u306e\u4fdd\u8b77\u5c64\uff08\u591a\u5c64\u9632\u5fa1\uff09\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u3067\u3088\u308a\u5805\u7262\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u69cb\u7bc9\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-33\">\u5b9f\u52d9\u3067\u4f7f\u3048\u308b\uff01intval()\u3092\u6d3b\u7528\u3057\u305f\u5b9f\u88c5\u30b5\u30f3\u30d7\u30eb\u96c6<\/h2>\n\n\n\n<p>PHP\u958b\u767a\u306e\u5b9f\u52d9\u3067\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3084\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u53d6\u5f97\u3057\u305f\u5024\u3092\u9069\u5207\u306b\u51e6\u7406\u3059\u308b\u5834\u9762\u304c\u983b\u7e41\u306b\u767a\u751f\u3057\u307e\u3059\u3002\u3053\u308c\u307e\u3067\u89e3\u8aac\u3057\u3066\u304d\u305f<code>intval()<\/code>\u95a2\u6570\u306e\u77e5\u8b58\u3092\u5b9f\u969b\u306e\u30b3\u30fc\u30c9\u3067\u6d3b\u7528\u3059\u308b\u305f\u3081\u306e\u3001\u3059\u3050\u306b\u4f7f\u3048\u308b\u5b9f\u88c5\u30b5\u30f3\u30d7\u30eb\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u4ee5\u4e0b\u306e\u30b5\u30f3\u30d7\u30eb\u306f\u3001Web\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u3067\u3088\u304f\u906d\u9047\u3059\u308b\u5178\u578b\u7684\u306a\u30b7\u30ca\u30ea\u30aa\u306b\u5bfe\u5fdc\u3057\u3066\u304a\u308a\u3001\u30b3\u30d4\u30fc\uff06\u30da\u30fc\u30b9\u30c8\u3067\u307b\u307c\u305d\u306e\u307e\u307e\u4f7f\u3048\u308b\u5f62\u3067\u63d0\u4f9b\u3057\u3066\u3044\u307e\u3059\u3002\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3084\u5805\u7262\u6027\u3092\u8003\u616e\u3057\u305f\u5b9f\u88c5\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u306e\u3067\u3001\u305c\u3072\u81ea\u5206\u306e\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u306b\u53d6\u308a\u5165\u308c\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-34\">\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\u3067\u306e\u5b89\u5168\u306a\u30d1\u30e9\u30e1\u30fc\u30bf\u53d6\u5f97\u30b3\u30fc\u30c9<\/h3>\n\n\n\n<p>Web\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u306b\u304a\u3044\u3066\u3001\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\uff08paging\uff09\u306f\u6b20\u304b\u305b\u306a\u3044\u6a5f\u80fd\u3067\u3059\u3002\u7279\u306b\u5927\u91cf\u306e\u30c7\u30fc\u30bf\u3092\u8868\u793a\u3059\u308b\u753b\u9762\u3067\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u304c\u6307\u5b9a\u3057\u305f\u30da\u30fc\u30b8\u756a\u53f7\u3092\u5b89\u5168\u306b\u51e6\u7406\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<code>intval()<\/code>\u95a2\u6570\u306f\u3001\u3053\u306e\u3088\u3046\u306a\u30b7\u30ca\u30ea\u30aa\u3067\u975e\u5e38\u306b\u91cd\u8981\u306a\u5f79\u5272\u3092\u679c\u305f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u4ee5\u4e0b\u306b\u3001\u5b9f\u52d9\u3067\u3059\u3050\u306b\u4f7f\u3048\u308b\u5b89\u5168\u306a\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\u306e\u30b3\u30fc\u30c9\u30b5\u30f3\u30d7\u30eb\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u5b89\u5168\u306a\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u53d6\u5f97\u3059\u308b\u95a2\u6570\n * \n * @param int $total_items \u7dcf\u30a2\u30a4\u30c6\u30e0\u6570\n * @param int $items_per_page 1\u30da\u30fc\u30b8\u3042\u305f\u308a\u306e\u30a2\u30a4\u30c6\u30e0\u6570\n * @param string $page_param \u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u540d\n * @return array \u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u60c5\u5831\u306e\u914d\u5217\n *\/\nfunction getPageParams($total_items, $items_per_page = 10, $page_param = 'page') {\n    \/\/ \u7dcf\u30da\u30fc\u30b8\u6570\u3092\u8a08\u7b97\n    $total_pages = ceil($total_items \/ $items_per_page);\n    $total_pages = max(1, $total_pages); \/\/ \u6700\u4f4e1\u30da\u30fc\u30b8\u78ba\u4fdd\n    \n    \/\/ GET\u30d1\u30e9\u30e1\u30fc\u30bf\u304b\u3089\u30da\u30fc\u30b8\u756a\u53f7\u3092\u53d6\u5f97\u3057\u3001\u6574\u6570\u306b\u5909\u63db\n    $current_page = isset($_GET[$page_param]) ? intval($_GET[$page_param]) : 1;\n    \n    \/\/ \u30da\u30fc\u30b8\u756a\u53f7\u306e\u7bc4\u56f2\u3092\u691c\u8a3c\n    if ($current_page &lt; 1) {\n        $current_page = 1; \/\/ 1\u672a\u6e80\u306f1\u30da\u30fc\u30b8\u76ee\u3068\u3059\u308b\n    }\n    \n    if ($current_page &gt; $total_pages) {\n        $current_page = $total_pages; \/\/ \u6700\u5927\u30da\u30fc\u30b8\u6570\u3092\u8d85\u3048\u306a\u3044\u3088\u3046\u306b\n    }\n    \n    \/\/ SQL\u306eLIMIT\u53e5\u3067\u4f7f\u7528\u3059\u308b\u30aa\u30d5\u30bb\u30c3\u30c8\u3092\u8a08\u7b97\n    $offset = ($current_page - 1) * $items_per_page;\n    \n    return [\n        'current_page' =&gt; $current_page,\n        'items_per_page' =&gt; $items_per_page,\n        'total_items' =&gt; $total_items,\n        'total_pages' =&gt; $total_pages,\n        'offset' =&gt; $offset,\n        'has_previous' =&gt; ($current_page &gt; 1),\n        'has_next' =&gt; ($current_page &lt; $total_pages),\n        'previous_page' =&gt; max(1, $current_page - 1),\n        'next_page' =&gt; min($total_pages, $current_page + 1)\n    ];\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u95a2\u6570\u306e\u5b9f\u969b\u306e\u4f7f\u7528\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u63a5\u7d9a\uff08PDO\u3092\u4f7f\u7528\uff09\n$pdo = new PDO('mysql:host=localhost;dbname=mystore', 'username', 'password');\n\n\/\/ \u7dcf\u5546\u54c1\u6570\u3092\u53d6\u5f97\n$stmt = $pdo-&gt;query(\"SELECT COUNT(*) FROM products\");\n$total_items = (int)$stmt-&gt;fetchColumn();\n\n\/\/ \u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u60c5\u5831\u3092\u53d6\u5f97\n$pagination = getPageParams($total_items, 12); \/\/ 1\u30da\u30fc\u30b812\u4ef6\u8868\u793a\n\n\/\/ \u5546\u54c1\u30c7\u30fc\u30bf\u3092\u53d6\u5f97\n$stmt = $pdo-&gt;prepare(\"\n    SELECT * FROM products \n    ORDER BY id DESC \n    LIMIT :limit OFFSET :offset\n\");\n$stmt-&gt;bindValue(':limit', $pagination['items_per_page'], PDO::PARAM_INT);\n$stmt-&gt;bindValue(':offset', $pagination['offset'], PDO::PARAM_INT);\n$stmt-&gt;execute();\n$products = $stmt-&gt;fetchAll(PDO::FETCH_ASSOC);\n\n\/\/ \u7d50\u679c\u3092\u30d3\u30e5\u30fc\u306b\u6e21\u3059\ninclude 'templates\/product_list.php';\n<\/pre>\n\n\n\n<p>\u30c6\u30f3\u30d7\u30ec\u30fc\u30c8\u30d5\u30a1\u30a4\u30eb\uff08product_list.php\uff09\u3067\u306e\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u30ea\u30f3\u30af\u306e\u8868\u793a\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">&lt;div class=\"products\"&gt;\n    &lt;?php foreach ($products as $product): ?&gt;\n        &lt;div class=\"product-item\"&gt;\n            &lt;h3&gt;&lt;?= htmlspecialchars($product['name']) ?&gt;&lt;\/h3&gt;\n            &lt;p&gt;&lt;?= htmlspecialchars($product['description']) ?&gt;&lt;\/p&gt;\n            &lt;div class=\"price\"&gt;\u00a5&lt;?= number_format($product['price']) ?&gt;&lt;\/div&gt;\n        &lt;\/div&gt;\n    &lt;?php endforeach; ?&gt;\n&lt;\/div&gt;\n\n&lt;div class=\"pagination\"&gt;\n    &lt;?php if ($pagination['has_previous']): ?&gt;\n        &lt;a href=\"?page=&lt;?= $pagination['previous_page'] ?&gt;\" class=\"prev\"&gt;\u524d\u3078&lt;\/a&gt;\n    &lt;?php else: ?&gt;\n        &lt;span class=\"prev disabled\"&gt;\u524d\u3078&lt;\/span&gt;\n    &lt;?php endif; ?&gt;\n    \n    &lt;?php for ($i = 1; $i &lt;= $pagination['total_pages']; $i++): ?&gt;\n        &lt;?php if ($i == $pagination['current_page']): ?&gt;\n            &lt;span class=\"current\"&gt;&lt;?= $i ?&gt;&lt;\/span&gt;\n        &lt;?php else: ?&gt;\n            &lt;a href=\"?page=&lt;?= $i ?&gt;\"&gt;&lt;?= $i ?&gt;&lt;\/a&gt;\n        &lt;?php endif; ?&gt;\n    &lt;?php endfor; ?&gt;\n    \n    &lt;?php if ($pagination['has_next']): ?&gt;\n        &lt;a href=\"?page=&lt;?= $pagination['next_page'] ?&gt;\" class=\"next\"&gt;\u6b21\u3078&lt;\/a&gt;\n    &lt;?php else: ?&gt;\n        &lt;span class=\"next disabled\"&gt;\u6b21\u3078&lt;\/span&gt;\n    &lt;?php endif; ?&gt;\n&lt;\/div&gt;\n<\/pre>\n\n\n\n<p><strong>\u3053\u306e\u30b3\u30fc\u30c9\u304c\u89e3\u6c7a\u3059\u308b\u4e3b\u306a\u554f\u984c\u70b9\uff1a<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\uff1a<\/strong> <code>intval()<\/code>\u3092\u4f7f\u7528\u3057\u3066\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3092\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u3053\u3068\u3067\u3001SQL\u30a4\u30f3\u30b8\u30a7\u30af\u30b7\u30e7\u30f3\u306a\u3069\u306e\u653b\u6483\u3092\u9632\u6b62\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u4e0d\u6b63\u306a\u30da\u30fc\u30b8\u756a\u53f7\uff1a<\/strong> \u8ca0\u306e\u5024\u3084\u6587\u5b57\u5217\u306a\u3069\u306e\u4e0d\u6b63\u306a\u5165\u529b\u5024\u3092\u9069\u5207\u306b\u51e6\u7406\u3057\u3001\u5e38\u306b\u6709\u52b9\u306a\u30da\u30fc\u30b8\u756a\u53f7\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u5b58\u5728\u3057\u306a\u3044\u30da\u30fc\u30b8\uff1a<\/strong> \u7dcf\u30da\u30fc\u30b8\u6570\u3092\u8d85\u3048\u308b\u30da\u30fc\u30b8\u756a\u53f7\u304c\u6307\u5b9a\u3055\u308c\u305f\u5834\u5408\u3001\u6700\u5927\u30da\u30fc\u30b8\u306b\u30ea\u30c0\u30a4\u30ec\u30af\u30c8\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u30e6\u30fc\u30b6\u30d3\u30ea\u30c6\u30a3\uff1a<\/strong> \u300c\u524d\u3078\u300d\u300c\u6b21\u3078\u300d\u30ea\u30f3\u30af\u306e\u72b6\u614b\u7ba1\u7406\u3084\u30da\u30fc\u30b8\u756a\u53f7\u306e\u5f37\u8abf\u8868\u793a\u306a\u3069\u3001\u4f7f\u3044\u3084\u3059\u3044UI\u3092\u63d0\u4f9b\u3057\u307e\u3059\u3002<\/li>\n<\/ol>\n\n\n\n<p><strong>\u6ce8\u610f\u70b9\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\uff1a<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>bindValue()<\/code>\u306b<code>PDO::PARAM_INT<\/code>\u3092\u6307\u5b9a\u3057\u3066\u3001\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u78ba\u5b9f\u306b\u6574\u6570\u3068\u3057\u3066\u30d0\u30a4\u30f3\u30c9\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li>\u30da\u30fc\u30b8\u30b5\u30a4\u30ba\uff08items_per_page\uff09\u306b\u3082\u4e0a\u9650\u3092\u8a2d\u3051\u308b\u3053\u3068\u3067\u3001\u6975\u7aef\u306b\u5927\u304d\u306a\u5024\u306b\u3088\u308b\u8ca0\u8377\u3092\u9632\u6b62\u3067\u304d\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u691c\u7d22\u6761\u4ef6\u304c\u3042\u308b\u5834\u5408\u306f\u3001\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u30ea\u30f3\u30af\u306b\u691c\u7d22\u30d1\u30e9\u30e1\u30fc\u30bf\u3082\u542b\u3081\u308b\u3088\u3046\u5b9f\u88c5\u3092\u62e1\u5f35\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li>\u30c6\u30b9\u30c8\u6642\u306b\u306f\u3001\u7279\u306b\u5883\u754c\u5024\uff08\u6700\u521d\u306e\u30da\u30fc\u30b8\u3001\u6700\u5f8c\u306e\u30da\u30fc\u30b8\uff09\u3084\u4e0d\u6b63\u306a\u5024\u3067\u306e\u52d5\u4f5c\u3092\u78ba\u8a8d\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u306e\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u5b9f\u88c5\u306f\u5c0f\u301c\u4e2d\u898f\u6a21\u306eWeb\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u5341\u5206\u5b9f\u7528\u7684\u3067\u3059\u304c\u3001\u5927\u898f\u6a21\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306fLaravel\u3084Symfony\u306a\u3069\u306e\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u304c\u63d0\u4f9b\u3059\u308b\u30da\u30fc\u30b8\u30cd\u30fc\u30b7\u30e7\u30f3\u6a5f\u80fd\u306e\u5229\u7528\u3082\u691c\u8a0e\u3059\u308b\u3068\u826f\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-35\">\u5546\u54c1\u6570\u91cf\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u30b5\u30cb\u30bf\u30a4\u30ba\u306e\u5b9f\u88c5\u4f8b<\/h3>\n\n\n\n<p>EC\u30b5\u30a4\u30c8\u3084\u30b7\u30e7\u30c3\u30d4\u30f3\u30b0\u30ab\u30fc\u30c8\u6a5f\u80fd\u3092\u5b9f\u88c5\u3059\u308b\u969b\u306b\u907f\u3051\u3066\u901a\u308c\u306a\u3044\u306e\u304c\u3001\u5546\u54c1\u6570\u91cf\u306e\u9069\u5207\u306a\u691c\u8a3c\u3067\u3059\u3002\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306f\u3055\u307e\u3056\u307e\u306a\u5f62\u5f0f\uff08\u8ca0\u6570\u3001\u6587\u5b57\u5217\u3001\u7570\u5e38\u306b\u5927\u304d\u306a\u5024\u306a\u3069\uff09\u306e\u53ef\u80fd\u6027\u304c\u3042\u308a\u3001\u3053\u308c\u3089\u3092\u6b63\u3057\u304f\u51e6\u7406\u3057\u306a\u3044\u3068\u30c7\u30fc\u30bf\u4e0d\u6574\u5408\u3084\u5728\u5eab\u7ba1\u7406\u306e\u554f\u984c\u306b\u3064\u306a\u304c\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u4ee5\u4e0b\u306b\u3001<code>intval()<\/code>\u3092\u6d3b\u7528\u3057\u305f\u5805\u7262\u306a\u5546\u54c1\u6570\u91cf\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u95a2\u6570\u306e\u5b9f\u88c5\u4f8b\u3092\u793a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u5546\u54c1\u6570\u91cf\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u30b5\u30cb\u30bf\u30a4\u30ba\u3092\u884c\u3046\u95a2\u6570\n * \n * @param mixed $quantity \u691c\u8a3c\u3059\u308b\u6570\u91cf\n * @param array $options \u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u30aa\u30d7\u30b7\u30e7\u30f3\n * @return array \u691c\u8a3c\u7d50\u679c\uff08valid, value, message\uff09\n *\/\nfunction validateQuantity($quantity, array $options = []) {\n    \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u30aa\u30d7\u30b7\u30e7\u30f3\n    $defaults = [\n        'min' =&gt; 1,        \/\/ \u6700\u5c0f\u6ce8\u6587\u6570\u91cf\n        'max' =&gt; 99,       \/\/ \u6700\u5927\u6ce8\u6587\u6570\u91cf\n        'stock' =&gt; null,   \/\/ \u5728\u5eab\u6570\uff08\u6307\u5b9a\u3055\u308c\u308c\u3070\u5728\u5eab\u30c1\u30a7\u30c3\u30af\u5b9f\u65bd\uff09\n        'required' =&gt; true \/\/ \u5fc5\u9808\u9805\u76ee\u304b\u3069\u3046\u304b\n    ];\n    \n    \/\/ \u30aa\u30d7\u30b7\u30e7\u30f3\u306e\u30de\u30fc\u30b8\n    $options = array_merge($defaults, $options);\n    \n    \/\/ \u7a7a\u5024\u306e\u30c1\u30a7\u30c3\u30af\n    if ($quantity === null || $quantity === '') {\n        if (!$options['required']) {\n            return ['valid' =&gt; true, 'value' =&gt; 0, 'message' =&gt; null];\n        }\n        return ['valid' =&gt; false, 'value' =&gt; null, 'message' =&gt; '\u6570\u91cf\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044'];\n    }\n    \n    \/\/ \u6570\u5024\u5f62\u5f0f\u30c1\u30a7\u30c3\u30af\n    if (!is_numeric($quantity)) {\n        return ['valid' =&gt; false, 'value' =&gt; null, 'message' =&gt; '\u6570\u91cf\u306f\u6570\u5024\u3067\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044'];\n    }\n    \n    \/\/ \u6574\u6570\u306b\u5909\u63db\n    $quantity = intval($quantity);\n    \n    \/\/ \u6700\u5c0f\u5024\u30c1\u30a7\u30c3\u30af\n    if ($quantity &lt; $options['min']) {\n        return [\n            'valid' =&gt; false, \n            'value' =&gt; null, \n            'message' =&gt; '\u6570\u91cf\u306f' . $options['min'] . '\u4ee5\u4e0a\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044'\n        ];\n    }\n    \n    \/\/ \u6700\u5927\u5024\u30c1\u30a7\u30c3\u30af\n    if ($quantity &gt; $options['max']) {\n        return [\n            'valid' =&gt; false, \n            'value' =&gt; null, \n            'message' =&gt; '\u6570\u91cf\u306f' . $options['max'] . '\u4ee5\u4e0b\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044'\n        ];\n    }\n    \n    \/\/ \u5728\u5eab\u30c1\u30a7\u30c3\u30af\uff08\u6307\u5b9a\u3055\u308c\u3066\u3044\u308b\u5834\u5408\uff09\n    if ($options['stock'] !== null &amp;&amp; $quantity &gt; $options['stock']) {\n        return [\n            'valid' =&gt; false, \n            'value' =&gt; null, \n            'message' =&gt; '\u5728\u5eab\u304c\u4e0d\u8db3\u3057\u3066\u3044\u307e\u3059\uff08\u5728\u5eab\u6570: ' . $options['stock'] . '\uff09'\n        ];\n    }\n    \n    \/\/ \u691c\u8a3c\u6210\u529f\n    return ['valid' =&gt; true, 'value' =&gt; $quantity, 'message' =&gt; null];\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u95a2\u6570\u3092\u5b9f\u969b\u306e\u30ab\u30fc\u30c8\u3078\u306e\u5546\u54c1\u8ffd\u52a0\u51e6\u7406\u3067\u4f7f\u7528\u3059\u308b\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30ab\u30fc\u30c8\u306b\u5546\u54c1\u3092\u8ffd\u52a0\u3059\u308b\u51e6\u7406\n * \n * @return array \u51e6\u7406\u7d50\u679c\n *\/\nfunction addToCart() {\n    \/\/ POST\u30ea\u30af\u30a8\u30b9\u30c8\u4ee5\u5916\u306f\u62d2\u5426\n    if ($_SERVER['REQUEST_METHOD'] !== 'POST') {\n        return ['success' =&gt; false, 'message' =&gt; '\u4e0d\u6b63\u306a\u30ea\u30af\u30a8\u30b9\u30c8\u65b9\u6cd5\u3067\u3059'];\n    }\n    \n    \/\/ \u5546\u54c1ID\u306e\u691c\u8a3c\n    $product_id = isset($_POST['product_id']) ? intval($_POST['product_id']) : 0;\n    if ($product_id &lt;= 0) {\n        return ['success' =&gt; false, 'message' =&gt; '\u5546\u54c1ID\u304c\u7121\u52b9\u3067\u3059'];\n    }\n    \n    \/\/ \u5546\u54c1\u60c5\u5831\u306e\u53d6\u5f97\n    $product = getProductById($product_id);\n    if (!$product) {\n        return ['success' =&gt; false, 'message' =&gt; '\u5546\u54c1\u304c\u898b\u3064\u304b\u308a\u307e\u305b\u3093'];\n    }\n    \n    \/\/ \u6570\u91cf\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\n    $quantity_result = validateQuantity(\n        $_POST['quantity'] ?? null,\n        [\n            'min' =&gt; 1,\n            'max' =&gt; 10,  \/\/ 1\u56de\u306e\u6ce8\u6587\u3067\u6700\u592710\u500b\u307e\u3067\n            'stock' =&gt; $product['stock']\n        ]\n    );\n    \n    \/\/ \u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u5931\u6557\u6642\n    if (!$quantity_result['valid']) {\n        return ['success' =&gt; false, 'message' =&gt; $quantity_result['message']];\n    }\n    \n    \/\/ \u30ab\u30fc\u30c8\u306b\u8ffd\u52a0\uff08\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u6e08\u307f\u306e\u5024\u3092\u4f7f\u7528\uff09\n    $quantity = $quantity_result['value'];\n    addItemToCart($product_id, $quantity);\n    \n    \/\/ \u6210\u529f\u30ec\u30b9\u30dd\u30f3\u30b9\n    return [\n        'success' =&gt; true,\n        'message' =&gt; $product['name'] . '\u3092\u30ab\u30fc\u30c8\u306b\u8ffd\u52a0\u3057\u307e\u3057\u305f',\n        'quantity' =&gt; $quantity,\n        'cart_count' =&gt; getCartItemCount()\n    ];\n}\n<\/pre>\n\n\n\n<p>\u4e0a\u8a18\u306e\u30b3\u30fc\u30c9\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u30dd\u30a4\u30f3\u30c8\u306b\u6ce8\u76ee\u3057\u3066\u304f\u3060\u3055\u3044\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><code>intval()<\/code>\u3092\u4f7f\u7528\u3057\u3066\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306e\u5546\u54c1ID\u3068\u6570\u91cf\u3092\u78ba\u5b9f\u306b\u6574\u6570\u306b\u5909\u63db<\/li>\n\n\n\n<li>\u6700\u5c0f\u5024\u30fb\u6700\u5927\u5024\u30c1\u30a7\u30c3\u30af\u306b\u3088\u308b\u9069\u5207\u306a\u7bc4\u56f2\u306e\u4fdd\u8a3c<\/li>\n\n\n\n<li>\u5728\u5eab\u6570\u3068\u306e\u6bd4\u8f03\u306b\u3088\u308b\u5728\u5eab\u4e0d\u8db3\u306e\u65e9\u671f\u691c\u51fa<\/li>\n\n\n\n<li>\u5404\u6bb5\u968e\u3067\u306e\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u306e\u5177\u4f53\u5316<\/li>\n\n\n\n<li>\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u6e08\u307f\u306e\u5024\u306e\u307f\u3092\u5f8c\u7d9a\u306e\u51e6\u7406\u3067\u4f7f\u7528<\/li>\n<\/ol>\n\n\n\n<p>\u5b9f\u969b\u306e\u30d5\u30a9\u30fc\u30e0\u5b9f\u88c5\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306aHTML\u3092\u4f7f\u7528\u3059\u308b\u3068\u30e6\u30fc\u30b6\u30d3\u30ea\u30c6\u30a3\u304c\u5411\u4e0a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">&lt;form action=\"\/cart\/add\" method=\"post\"&gt;\n    &lt;input type=\"hidden\" name=\"product_id\" value=\"&lt;?= $product['id'] ?&gt;\"&gt;\n    \n    &lt;div class=\"quantity-selector\"&gt;\n        &lt;label for=\"quantity\"&gt;\u6570\u91cf:&lt;\/label&gt;\n        &lt;select name=\"quantity\" id=\"quantity\"&gt;\n            &lt;?php\n            \/\/ \u5728\u5eab\u6570\u3068\u6700\u5927\u6ce8\u6587\u6570\u306e\u5c0f\u3055\u3044\u65b9\u3092\u4e0a\u9650\u3068\u3059\u308b\n            $max_allowed = min(10, $product['stock']);\n            for ($i = 1; $i &lt;= $max_allowed; $i++) {\n                echo '&lt;option value=\"' . $i . '\"&gt;' . $i . '&lt;\/option&gt;';\n            }\n            ?&gt;\n        &lt;\/select&gt;\n        &lt;span class=\"stock-info\"&gt;\uff08\u5728\u5eab: &lt;?= $product['stock'] ?&gt;\u500b\uff09&lt;\/span&gt;\n    &lt;\/div&gt;\n    \n    &lt;button type=\"submit\"&gt;\u30ab\u30fc\u30c8\u306b\u8ffd\u52a0&lt;\/button&gt;\n&lt;\/form&gt;\n<\/pre>\n\n\n\n<p><strong>\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3068\u5b9f\u7528\u6027\u306e\u30d0\u30e9\u30f3\u30b9<\/strong><\/p>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u8ffd\u52a0\u5bfe\u7b56\u3082\u8003\u616e\u3059\u308b\u3068\u826f\u3044\u3067\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>CSRF\u30c8\u30fc\u30af\u30f3\u691c\u8a3c<\/strong> \u2013 \u30d5\u30a9\u30fc\u30e0\u306e\u6539\u3056\u3093\u3084\u4e0d\u6b63\u9001\u4fe1\u3092\u9632\u6b62<\/li>\n\n\n\n<li><strong>\u540c\u6642\u5b9f\u884c\u5236\u5fa1<\/strong> \u2013 \u5728\u5eab\u6570\u306e\u540c\u6642\u66f4\u65b0\u306b\u3088\u308b\u7af6\u5408\u3092\u9632\u6b62\uff08\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u4f7f\u7528\uff09<\/li>\n\n\n\n<li><strong>\u30ec\u30fc\u30c8\u5236\u9650<\/strong> \u2013 \u77ed\u6642\u9593\u3067\u306e\u5927\u91cf\u30ea\u30af\u30a8\u30b9\u30c8\u306b\u3088\u308bDoS\u653b\u6483\u5bfe\u7b56<\/li>\n<\/ol>\n\n\n\n<p>\u307e\u305f\u3001Ajax\u3092\u4f7f\u7528\u3057\u305f\u975e\u540c\u671f\u66f4\u65b0\u3092\u5b9f\u88c5\u3059\u308b\u5834\u5408\u3082\u3001\u540c\u69d8\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u304c\u5fc5\u8981\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30d5\u30ed\u30f3\u30c8\u30a8\u30f3\u30c9\u3067\u306e\u4e8b\u524d\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\uff08UX\u5411\u4e0a\u306e\u305f\u3081\uff09\ndocument.getElementById('quantity').addEventListener('change', function() {\n    const quantity = parseInt(this.value, 10);\n    const stock = parseInt(this.dataset.stock, 10);\n    \n    if (isNaN(quantity) || quantity &lt; 1) {\n        alert('\u6570\u91cf\u306f1\u4ee5\u4e0a\u306e\u6570\u5024\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044');\n        this.value = 1;\n    } else if (quantity &gt; stock) {\n        alert('\u5728\u5eab\u304c\u4e0d\u8db3\u3057\u3066\u3044\u307e\u3059');\n        this.value = stock;\n    }\n});\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306b<code>intval()<\/code>\u3092\u6838\u3068\u3057\u305f\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3068\u30b5\u30cb\u30bf\u30a4\u30ba\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u3067\u3001\u30e6\u30fc\u30b6\u30fc\u306e\u5165\u529b\u30df\u30b9\u306b\u3088\u308b\u30a8\u30e9\u30fc\u3092\u9632\u304e\u3064\u3064\u3001\u4e0d\u6b63\u306a\u5165\u529b\u306b\u3088\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\u3082\u4f4e\u6e1b\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-36\">ID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u306b\u304a\u3051\u308b\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30d1\u30bf\u30fc\u30f3<\/h3>\n\n\n\n<p>\u591a\u304f\u306eWeb\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306f\u3001URL\u306b\u30ea\u30bd\u30fc\u30b9\u306eID\uff08\u5546\u54c1ID\u3001\u8a18\u4e8bID\u3001\u30e6\u30fc\u30b6\u30fcID\u306a\u3069\uff09\u3092\u542b\u3081\u308bID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u304c\u4f7f\u308f\u308c\u3066\u3044\u307e\u3059\u3002\u4f8b\u3048\u3070 <code>\/products\/123<\/code> \u306e\u3088\u3046\u306aURL\u3067\u306f\u3001\u300c123\u300d\u304c\u5546\u54c1ID\u3092\u8868\u3057\u307e\u3059\u3002\u3053\u306e\u3088\u3046\u306a\u30d1\u30bf\u30fc\u30f3\u3092\u5b89\u5168\u306b\u5b9f\u88c5\u3059\u308b\u305f\u3081\u306b\u306f\u3001<code>intval()<\/code>\u95a2\u6570\u304c\u975e\u5e38\u306b\u91cd\u8981\u306a\u5f79\u5272\u3092\u679c\u305f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>\u306a\u305cID\u306e\u6574\u6570\u5909\u63db\u304c\u91cd\u8981\u306a\u306e\u304b\uff1f<\/strong><\/p>\n\n\n\n<p>\u30e6\u30fc\u30b6\u30fc\u306fURL\u3092\u76f4\u63a5\u7de8\u96c6\u3067\u304d\u308b\u305f\u3081\u3001\u4e0d\u6b63\u306a\u5024\uff08\u6587\u5b57\u5217\u3001\u8ca0\u6570\u3001\u6975\u7aef\u306b\u5927\u304d\u306a\u5024\u306a\u3069\uff09\u3092\u5165\u529b\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u5024\u3092\u305d\u306e\u307e\u307e\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u306b\u4f7f\u7528\u3059\u308b\u3068\u3001\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\u3084\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u554f\u984c\u306b\u3064\u306a\u304c\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u4ee5\u4e0b\u306b\u3001ID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3092\u5b89\u5168\u306b\u5b9f\u88c5\u3059\u308b\u305f\u3081\u306e\u30b3\u30fc\u30c9\u30d1\u30bf\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * URL\u304b\u3089ID\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u5b89\u5168\u306b\u53d6\u5f97\u3059\u308b\u95a2\u6570\n * \n * @param string $param_name \u30d1\u30e9\u30e1\u30fc\u30bf\u540d\n * @return int|null \u6574\u6570ID\u3001\u7121\u52b9\u306a\u5834\u5408\u306fnull\n *\/\nfunction getSafeId($param_name = 'id') {\n    \/\/ URL\u304b\u3089\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u53d6\u5f97\uff08\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u307e\u305f\u306f\u30d1\u30b9\u30d1\u30e9\u30e1\u30fc\u30bf\uff09\n    $id = $_GET[$param_name] ?? null;\n    \n    \/\/ \u6570\u5024\u3067\u306a\u3044\u5834\u5408\u306fnull\u3092\u8fd4\u3059\n    if (!is_numeric($id)) {\n        return null;\n    }\n    \n    \/\/ \u6574\u6570\u306b\u5909\u63db\n    $id = intval($id);\n    \n    \/\/ 0\u307e\u305f\u306f\u8ca0\u306e\u5024\u306f\u7121\u52b9\u306aID\u3068\u307f\u306a\u3059\n    if ($id &lt;= 0) {\n        return null;\n    }\n    \n    return $id;\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u95a2\u6570\u3092\u4f7f\u3063\u3066\u3001\u5546\u54c1\u8a73\u7d30\u30da\u30fc\u30b8\u306a\u3069\u3092\u5b9f\u88c5\u3059\u308b\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u5546\u54c1\u8a73\u7d30\u30da\u30fc\u30b8\u306e\u30b3\u30f3\u30c8\u30ed\u30fc\u30e9\u30fc\n *\/\nfunction showProductPage() {\n    \/\/ URL\u304b\u3089ID\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u5b89\u5168\u306b\u53d6\u5f97\n    $product_id = getSafeId('product_id');\n    \n    \/\/ \u7121\u52b9\u306aID\u306e\u5834\u5408\u306f404\u30a8\u30e9\u30fc\n    if ($product_id === null) {\n        header(\"HTTP\/1.0 404 Not Found\");\n        include 'templates\/404.php';\n        exit;\n    }\n    \n    \/\/ \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u5546\u54c1\u60c5\u5831\u3092\u53d6\u5f97\n    $pdo = connectDatabase();\n    $stmt = $pdo-&gt;prepare(\"SELECT * FROM products WHERE id = ?\");\n    $stmt-&gt;execute([$product_id]);\n    $product = $stmt-&gt;fetch(PDO::FETCH_ASSOC);\n    \n    \/\/ \u5546\u54c1\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u3082404\u30a8\u30e9\u30fc\n    if (!$product) {\n        header(\"HTTP\/1.0 404 Not Found\");\n        include 'templates\/404.php';\n        exit;\n    }\n    \n    \/\/ SEO\u5bfe\u7b56\uff1aURL\u306e\u6b63\u898f\u5316\uff08\u5546\u54c1\u540d\u306e\u30b9\u30e9\u30b0\u3092\u542b\u3080URL\u3078\u30ea\u30c0\u30a4\u30ec\u30af\u30c8\uff09\n    $slug = createSlug($product['name']);\n    $canonical_url = \"\/products\/{$product_id}\/{$slug}\";\n    $current_url = $_SERVER['REQUEST_URI'];\n    \n    if ($current_url !== $canonical_url) {\n        header(\"Location: {$canonical_url}\", true, 301);\n        exit;\n    }\n    \n    \/\/ \u30c6\u30f3\u30d7\u30ec\u30fc\u30c8\u3092\u8868\u793a\n    include 'templates\/product_detail.php';\n}\n<\/pre>\n\n\n\n<p><strong>RESTful\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3067\u306eID\u62bd\u51fa<\/strong><\/p>\n\n\n\n<p>\u3088\u308a\u73fe\u4ee3\u7684\u306aRESTful\u306aURL\uff08\u4f8b: <code>\/products\/123<\/code>\uff09\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\u306f\u3001URL\u30d1\u30b9\u304b\u3089\u76f4\u63a5ID\u3092\u62bd\u51fa\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * RESTful\u306aURL\u30d1\u30b9\u304b\u3089ID\u3092\u62bd\u51fa\u3059\u308b\n * \n * @param string $pattern ID\u3092\u62bd\u51fa\u3059\u308b\u6b63\u898f\u8868\u73fe\u30d1\u30bf\u30fc\u30f3\n * @param string $uri \u30ea\u30af\u30a8\u30b9\u30c8URI\n * @return int|null \u6709\u52b9\u306aID\u307e\u305f\u306fnull\n *\/\nfunction extractIdFromPath($pattern, $uri) {\n    if (preg_match($pattern, $uri, $matches)) {\n        if (isset($matches[1]) &amp;&amp; is_numeric($matches[1])) {\n            $id = intval($matches[1]);\n            return ($id &gt; 0) ? $id : null;\n        }\n    }\n    return null;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$request_uri = $_SERVER['REQUEST_URI'];\n$product_id = extractIdFromPath('#^\/products\/(\\d+)#', $request_uri);\n\nif ($product_id === null) {\n    \/\/ 404\u30a8\u30e9\u30fc\u51e6\u7406\n}\n<\/pre>\n\n\n\n<p><strong>\u30b7\u30f3\u30d7\u30eb\u306a\u30eb\u30fc\u30bf\u30fc\u3092\u5b9f\u88c5\u3059\u308b\u4f8b<\/strong><\/p>\n\n\n\n<p>\u5c0f\u301c\u4e2d\u898f\u6a21\u306e\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30b7\u30f3\u30d7\u30eb\u306a\u30eb\u30fc\u30bf\u30fc\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u3067\u3001ID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3092\u3088\u308a\u4f53\u7cfb\u7684\u306b\u6271\u3048\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30b7\u30f3\u30d7\u30eb\u306a\u30eb\u30fc\u30bf\u30fc\u306e\u4f8b\n *\/\nclass Router {\n    private $routes = [];\n    \n    \/**\n     * GET\u30eb\u30fc\u30c8\u3092\u8ffd\u52a0\n     *\/\n    public function get($pattern, $handler) {\n        $this-&gt;routes['GET'][$pattern] = $handler;\n    }\n    \n    \/**\n     * POST\u30eb\u30fc\u30c8\u3092\u8ffd\u52a0\n     *\/\n    public function post($pattern, $handler) {\n        $this-&gt;routes['POST'][$pattern] = $handler;\n    }\n    \n    \/**\n     * \u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3092\u5b9f\u884c\n     *\/\n    public function dispatch() {\n        $method = $_SERVER['REQUEST_METHOD'];\n        $uri = parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH);\n        \n        foreach ($this-&gt;routes[$method] ?? [] as $pattern =&gt; $handler) {\n            if (preg_match('#^' . $pattern . '$#', $uri, $matches)) {\n                \/\/ \u6570\u5024\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u62bd\u51fa\u3057\u3066\u6574\u6570\u306b\u5909\u63db\n                array_shift($matches); \/\/ \u6700\u521d\u306e\u5b8c\u5168\u4e00\u81f4\u3092\u524a\u9664\n                \n                \/\/ \u6570\u5024\u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u307f\u3092\u6574\u6570\u306b\u5909\u63db\n                $params = [];\n                foreach ($matches as $match) {\n                    $params[] = is_numeric($match) ? intval($match) : $match;\n                }\n                \n                \/\/ \u30cf\u30f3\u30c9\u30e9\u3092\u5b9f\u884c\n                call_user_func_array($handler, $params);\n                return;\n            }\n        }\n        \n        \/\/ \u30de\u30c3\u30c1\u3059\u308b\u30eb\u30fc\u30c8\u304c\u306a\u3044\u5834\u5408\u306f404\n        header(\"HTTP\/1.0 404 Not Found\");\n        include 'templates\/404.php';\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$router = new Router();\n\n\/\/ \u5546\u54c1\u8a73\u7d30\u30da\u30fc\u30b8\u306e\u30eb\u30fc\u30c8\u5b9a\u7fa9\n$router-&gt;get('products\/(\\d+)(?:\/[\\w-]*)?', function($id) {\n    \/\/ $id\u306f\u65e2\u306bintval()\u3067\u6574\u6570\u5909\u63db\u6e08\u307f\n    $product = getProductById($id);\n    \n    if (!$product) {\n        header(\"HTTP\/1.0 404 Not Found\");\n        include 'templates\/404.php';\n        exit;\n    }\n    \n    \/\/ SEO\u5bfe\u7b56\uff1a\u6b63\u898fURL\u30c1\u30a7\u30c3\u30af\n    $slug = createSlug($product['name']);\n    $canonical_url = \"\/products\/{$id}\/{$slug}\";\n    \n    if ($_SERVER['REQUEST_URI'] !== $canonical_url) {\n        header(\"Location: {$canonical_url}\", true, 301);\n        exit;\n    }\n    \n    include 'templates\/product_detail.php';\n});\n\n\/\/ \u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u5b9f\u884c\n$router-&gt;dispatch();\n<\/pre>\n\n\n\n<p><strong>\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/strong><\/p>\n\n\n\n<p>ID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3092\u5b9f\u88c5\u3059\u308b\u969b\u306f\u3001\u4ee5\u4e0b\u306e\u70b9\u306b\u6ce8\u610f\u3057\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5fc5\u305a\u6574\u6570\u5909\u63db<\/strong>: URL\u304b\u3089\u53d6\u5f97\u3057\u305fID\u306f\u5fc5\u305a<code>intval()<\/code>\u3067\u6574\u6570\u306b\u5909\u63db\u3059\u308b<\/li>\n\n\n\n<li><strong>\u7121\u52b9\u306a\u5024\u306e\u51e6\u7406<\/strong>: \u8ca0\u6570\u3084\u30bc\u30ed\u3001\u975e\u6570\u5024\u306a\u3069\u7121\u52b9\u306aID\u306f\u65e9\u671f\u306b\u691c\u51fa\u3057404\u3092\u8fd4\u3059<\/li>\n\n\n\n<li><strong>\u5b58\u5728\u30c1\u30a7\u30c3\u30af<\/strong>: \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u3067ID\u306e\u5b58\u5728\u3092\u78ba\u8a8d\u3057\u3001\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u3082404\u3092\u8fd4\u3059<\/li>\n\n\n\n<li><strong>SEO\u5bfe\u7b56<\/strong>: \u540c\u4e00\u30b3\u30f3\u30c6\u30f3\u30c4\u3078\u306e\u8907\u6570URL\u30a2\u30af\u30bb\u30b9\u3092\u9632\u3050\u305f\u3081\u3001\u6b63\u898fURL\u3078\u30ea\u30c0\u30a4\u30ec\u30af\u30c8<\/li>\n\n\n\n<li><strong>\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8<\/strong>: \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u306b\u306f\u5fc5\u305a\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u3092\u4f7f\u7528<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d1\u30bf\u30fc\u30f3\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u3067\u3001ID\u30d9\u30fc\u30b9\u306e\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3092\u5b89\u5168\u304b\u3064\u52b9\u7387\u7684\u306b\u5b9f\u88c5\u3067\u304d\u307e\u3059\u3002\u7279\u306b<code>intval()<\/code>\u306b\u3088\u308b\u6574\u6570\u5909\u63db\u306f\u3001\u4e0d\u6b63\u306aURL\u30d1\u30e9\u30e1\u30fc\u30bf\u306b\u3088\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30ea\u30b9\u30af\u3092\u5927\u5e45\u306b\u8efd\u6e1b\u3059\u308b\u57fa\u672c\u7684\u304b\u3064\u91cd\u8981\u306a\u5bfe\u7b56\u3067\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-37\">PHP 8\u4ee5\u964d\u306eintval()\u306e\u5909\u66f4\u70b9\u3068\u4e92\u63db\u6027\u3078\u306e\u5f71\u97ff<\/h2>\n\n\n\n<p>PHP 8\u306f\u3001\u8a00\u8a9e\u5168\u4f53\u306e\u4e00\u8cab\u6027\u3068\u578b\u5b89\u5168\u6027\u306e\u5411\u4e0a\u3092\u76ee\u6307\u3057\u305f\u5927\u578b\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u3067\u3059\u3002\u3053\u306e\u5909\u66f4\u306b\u4f34\u3044\u3001<code>intval()<\/code>\u95a2\u6570\u306e\u6319\u52d5\u306b\u3082\u3044\u304f\u3064\u304b\u306e\u91cd\u8981\u306a\u5909\u66f4\u304c\u52a0\u3048\u3089\u308c\u307e\u3057\u305f\u3002\u3053\u308c\u3089\u306e\u5909\u66f4\u3092\u7406\u89e3\u3057\u3001\u9069\u5207\u306b\u5bfe\u5fdc\u3059\u308b\u3053\u3068\u3067\u3001PHP 7\u304b\u3089PHP 8\u3078\u306e\u79fb\u884c\u3092\u30b9\u30e0\u30fc\u30ba\u306b\u884c\u3046\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>PHP 8.0\u30688.1\u306e\u30ea\u30ea\u30fc\u30b9\u3067\u306f\u3001<code>intval()<\/code>\u95a2\u6570\u306b\u95a2\u9023\u3057\u3066\u7279\u306b\u6ce8\u610f\u3059\u3079\u304d\u5909\u66f4\u70b9\u304c\u3044\u304f\u3064\u304b\u3042\u308a\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u5909\u66f4\u306f\u3001\u7279\u306b\u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u51e6\u7406\u3092\u884c\u3046\u30b3\u30fc\u30c9\u306b\u5f71\u97ff\u3092\u4e0e\u3048\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-38\">\u6700\u65b0\u30d0\u30fc\u30b8\u30e7\u30f3\u3067\u306e\u4ed5\u69d8\u5909\u66f4\u3068\u5f8c\u65b9\u4e92\u63db\u6027\u306b\u3064\u3044\u3066<\/h3>\n\n\n\n<p>PHP 8\u3067\u306f\u8a00\u8a9e\u5168\u4f53\u306e\u4e00\u8cab\u6027\u3068\u578b\u5b89\u5168\u6027\u306e\u5411\u4e0a\u3092\u76ee\u6307\u3057\u305f\u591a\u304f\u306e\u5909\u66f4\u304c\u884c\u308f\u308c\u307e\u3057\u305f\u304c\u3001\u305d\u306e\u4e00\u74b0\u3068\u3057\u3066<code>intval()<\/code>\u95a2\u6570\u306e\u6319\u52d5\u306b\u3082\u91cd\u8981\u306a\u5909\u66f4\u304c\u52a0\u3048\u3089\u308c\u307e\u3057\u305f\u3002\u65e2\u5b58\u306ePHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u65b0\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u79fb\u884c\u3059\u308b\u969b\u306b\u306f\u3001\u3053\u308c\u3089\u306e\u5909\u66f4\u70b9\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<p><strong>\u914d\u5217\u306e\u6271\u3044\u306b\u95a2\u3059\u308b\u5909\u66f4<\/strong><\/p>\n\n\n\n<p>\u6700\u3082\u9855\u8457\u306a\u5909\u66f4\u70b9\u306f\u3001\u914d\u5217\u3092<code>intval()<\/code>\u306b\u6e21\u3057\u305f\u969b\u306e\u6319\u52d5\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$array = [1, 2, 3];\n\n\/\/ PHP 7.3\necho intval($array); \/\/ \u51fa\u529b: 1\uff08\u8b66\u544a\u306a\u3057\uff09\n\n\/\/ PHP 7.4\necho intval($array); \/\/ \u8b66\u544a: Array to int conversion + \u51fa\u529b: 1\n\n\/\/ PHP 8.0\u4ee5\u964d\necho intval($array); \/\/ \u8b66\u544a: Array to int conversion + \u51fa\u529b: 0\n<\/pre>\n\n\n\n<p>PHP 8\u4ee5\u964d\u3067\u306f\u3001\u914d\u5217\u304c\u6574\u6570\u50240\u306b\u5909\u63db\u3055\u308c\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f\u3002\u3053\u308c\u306f\u91cd\u8981\u306a\u5909\u66f4\u70b9\u3067\u3042\u308a\u3001\u6761\u4ef6\u5206\u5c90\u3067\u4f7f\u7528\u3057\u3066\u3044\u305f\u5834\u5408\u306b\u7279\u306b\u5f71\u97ff\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5371\u967a\u306a\u30b3\u30fc\u30c9\u4f8b\nfunction isValid($value) {\n    return intval($value) &gt; 0;\n}\n\n$data = [1, 2, 3];\n\n\/\/ PHP 7\u3067\u306f true \u304c\u8fd4\u3055\u308c\u308b\u304c\u3001PHP 8\u3067\u306f false \u304c\u8fd4\u3055\u308c\u308b\nif (isValid($data)) {\n    \/\/ \u3053\u306e\u51e6\u7406\u306fPHP 7\u3067\u306f\u5b9f\u884c\u3055\u308c\u308b\u304c\u3001PHP 8\u3067\u306f\u5b9f\u884c\u3055\u308c\u306a\u3044\n}\n<\/pre>\n\n\n\n<p><strong>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u6271\u3044\u306b\u95a2\u3059\u308b\u5909\u66f4<\/strong><\/p>\n\n\n\n<p>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308b\u6319\u52d5\u3082\u5909\u66f4\u3055\u308c\u3066\u3044\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$obj = new stdClass();\n\n\/\/ PHP 7.3\necho intval($obj); \/\/ \u51fa\u529b: 1\uff08\u8b66\u544a\u306a\u3057\uff09\n\n\/\/ PHP 7.4\u4ee5\u964d\necho intval($obj); \/\/ \u8b66\u544a: Object of class stdClass to int conversion + \u51fa\u529b: 1\n<\/pre>\n\n\n\n<p>PHP 7.4\u304b\u3089\u306f\u8b66\u544a\u304c\u767a\u751f\u3059\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f\u304c\u3001\u623b\u308a\u5024\u306f\u5909\u308f\u3089\u305a1\u3067\u3059\u3002\u3057\u304b\u3057\u8b66\u544a\u304c\u8868\u793a\u3055\u308c\u308b\u3053\u3068\u3067\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u52d5\u4f5c\u306b\u5f71\u97ff\u304c\u51fa\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30a8\u30e9\u30fc\u8868\u793a\u8a2d\u5b9a\u306b\u3088\u3063\u3066\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u306b\u8b66\u544a\u304c\u898b\u3048\u3066\u3057\u307e\u3046<\/li>\n\n\n\n<li>\u30a8\u30e9\u30fc\u30ed\u30b0\u304c\u80a5\u5927\u5316\u3059\u308b<\/li>\n\n\n\n<li>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30e9\u30fc\u304c\u610f\u56f3\u3057\u306a\u3044\u52d5\u4f5c\u3092\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308b<\/li>\n<\/ol>\n\n\n\n<p>\u7279\u306b\u8208\u5473\u6df1\u3044\u306e\u306f\u3001<code>__toString()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u5b9f\u88c5\u3057\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u6271\u3044\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class Number {\n    public function __toString() {\n        return \"42\";\n    }\n}\n$num = new Number();\n\n\/\/ PHP 7.2\necho intval($num); \/\/ \u51fa\u529b: 0\n\n\/\/ PHP 7.3\necho intval($num); \/\/ \u51fa\u529b: 1\n\n\/\/ PHP 7.4\u4ee5\u964d\necho intval($num); \/\/ \u8b66\u544a: Object of class Number to int conversion + \u51fa\u529b: 1\n<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306bPHP\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u6319\u52d5\u304c\u7570\u306a\u308b\u305f\u3081\u3001\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u76f4\u63a5<code>intval()<\/code>\u306b\u6e21\u3059\u3053\u3068\u306f\u907f\u3051\u308b\u3079\u304d\u3067\u3059\u3002<\/p>\n\n\n\n<p><strong>\u4e92\u63db\u6027\u554f\u984c\u3078\u306e\u5bfe\u5fdc\u7b56<\/strong><\/p>\n\n\n\n<p>PHP 8\u3078\u306e\u79fb\u884c\u6642\u306b\u767a\u751f\u3059\u308b\u53ef\u80fd\u6027\u306e\u3042\u308b\u554f\u984c\u306b\u5bfe\u51e6\u3059\u308b\u305f\u3081\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u5bfe\u7b56\u3092\u691c\u8a0e\u3057\u3066\u304f\u3060\u3055\u3044\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u30e9\u30c3\u30d1\u30fc\u306e\u5c0e\u5165<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30d0\u30fc\u30b8\u30e7\u30f3\u4e92\u63db\u6027\u306e\u3042\u308b\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u95a2\u6570\n * \n * @param mixed $value \u5909\u63db\u3059\u308b\u5024\n * @param int $default \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\n * @return int \u5909\u63db\u5f8c\u306e\u6574\u6570\u5024\n *\/\nfunction safeIntval($value, $default = 0) {\n    \/\/ \u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u8fd4\u3059\n    if (is_array($value) || is_object($value)) {\n        return $default;\n    }\n    \n    return intval($value);\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$id = safeIntval($_GET['id'], 0);\n$count = safeIntval($someValue, 1);\n<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u9069\u5207\u306a\u5909\u63db\u51e6\u7406<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u9069\u5207\u306b\u6574\u6570\u306b\u5909\u63db\u3059\u308b\n * \n * @param object $object \u5909\u63db\u3059\u308b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\n * @return int \u5909\u63db\u5f8c\u306e\u6574\u6570\u5024\n *\/\nfunction objectToInt($object) {\n    if (!is_object($object)) {\n        throw new InvalidArgumentException('Not an object');\n    }\n    \n    \/\/ __toString()\u30e1\u30bd\u30c3\u30c9\u304c\u3042\u308c\u3070\u5229\u7528\n    if (method_exists($object, '__toString')) {\n        return intval($object-&gt;__toString());\n    }\n    \n    \/\/ toInt()\u306a\u3069\u306e\u30ab\u30b9\u30bf\u30e0\u30e1\u30bd\u30c3\u30c9\u304c\u3042\u308c\u3070\u5229\u7528\n    if (method_exists($object, 'toInt')) {\n        return $object-&gt;toInt();\n    }\n    \n    \/\/ \u5909\u63db\u3067\u304d\u306a\u3044\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\n    return 0;\n}\n<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u578b\u30c1\u30a7\u30c3\u30af\u306e\u5c0e\u5165<\/strong><\/li>\n<\/ol>\n\n\n\n<p>PHP 8\u3078\u306e\u79fb\u884c\u3092\u6a5f\u306b\u3001\u3088\u308a\u53b3\u683c\u306a\u578b\u30c1\u30a7\u30c3\u30af\u3092\u5c0e\u5165\u3059\u308b\u3053\u3068\u3092\u691c\u8a0e\u3057\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PHP 7.4\u4ee5\u964d\nfunction processId(int $id): void {\n    \/\/ $id\u306f\u5fc5\u305a\u6574\u6570\u578b\u306a\u306e\u3067\u3001intval()\u306f\u4e0d\u8981\n    \/\/ \u51e6\u7406...\n}\n\n\/\/ \u547c\u3073\u51fa\u3057\u5074\n$input = $_GET['id'] ?? '';\nif (is_numeric($input)) {\n    processId((int)$input); \/\/ \u660e\u793a\u7684\u306b\u30ad\u30e3\u30b9\u30c8\n} else {\n    \/\/ \u30a8\u30e9\u30fc\u51e6\u7406\n}\n<\/pre>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\">\n<li><strong>\u65e2\u5b58\u30b3\u30fc\u30c9\u306e\u78ba\u8a8d\u3068\u4fee\u6b63<\/strong><\/li>\n<\/ol>\n\n\n\n<p>\u65e2\u5b58\u306e\u30b3\u30fc\u30c9\u30d9\u30fc\u30b9\u3092\u78ba\u8a8d\u3057\u3001\u554f\u984c\u306e\u3042\u308b\u7b87\u6240\u3092\u7279\u5b9a\u3059\u308b\u306b\u306f\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30a8\u30e9\u30fc\u30ec\u30dd\u30fc\u30c8\u30ec\u30d9\u30eb\u3092<code>E_ALL<\/code>\u306b\u8a2d\u5b9a\u3057\u3066\u30c6\u30b9\u30c8\u5b9f\u884c<\/li>\n\n\n\n<li>\u9759\u7684\u89e3\u6790\u30c4\u30fc\u30eb\uff08PHPStan, Psalm\uff09\u3092\u4f7f\u7528\u3057\u3066\u6f5c\u5728\u7684\u306a\u554f\u984c\u3092\u691c\u51fa<\/li>\n\n\n\n<li><code>intval()<\/code>\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u3059\u3079\u3066\u306e\u7b87\u6240\u3092\u30b3\u30fc\u30c9\u691c\u7d22\u3067\u7279\u5b9a<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5bfe\u7b56\u3092\u8b1b\u3058\u308b\u3053\u3068\u3067\u3001PHP 8\u3078\u306e\u79fb\u884c\u6642\u306b\u767a\u751f\u3059\u308b\u53ef\u80fd\u6027\u306e\u3042\u308b\u4e92\u63db\u6027\u554f\u984c\u3092\u6700\u5c0f\u9650\u306b\u6291\u3048\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-39\">PHP 8\u306e\u53b3\u683c\u306a\u578b\u30c1\u30a7\u30c3\u30af\u306b\u5bfe\u5fdc\u3059\u308bintval()\u306e\u4f7f\u3044\u65b9<\/h3>\n\n\n\n<p>PHP 8\u3067\u306f\u578b\u30b7\u30b9\u30c6\u30e0\u304c\u5927\u5e45\u306b\u5f37\u5316\u3055\u308c\u3001\u3088\u308a\u53b3\u683c\u306a\u578b\u30c1\u30a7\u30c3\u30af\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3057\u305f\u3002\u3053\u308c\u306b\u4f34\u3044\u3001<code>intval()<\/code>\u95a2\u6570\u306e\u4f7f\u3044\u65b9\u306b\u3082\u5909\u5316\u304c\u6c42\u3081\u3089\u308c\u307e\u3059\u3002PHP 8\u306e\u578b\u30b7\u30b9\u30c6\u30e0\u3092\u6d3b\u304b\u3057\u3066\u3001\u3088\u308a\u5805\u7262\u306a\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u305f\u3081\u306e\u65b9\u6cd5\u3092\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<p><strong>\u578b\u5ba3\u8a00\u3068\u306e\u9023\u643a<\/strong><\/p>\n\n\n\n<p>PHP 8\u3067\u306f\u578b\u5ba3\u8a00\uff08\u30bf\u30a4\u30d7\u30d2\u30f3\u30c6\u30a3\u30f3\u30b0\uff09\u304c\u3055\u3089\u306b\u5f37\u5316\u3055\u308c\u307e\u3057\u305f\u3002\u3053\u308c\u3092<code>intval()<\/code>\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u578b\u5b89\u5168\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u304c\u66f8\u3051\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PHP 8\u306e\u578b\u5ba3\u8a00\u3092\u6d3b\u7528\u3057\u305f\u95a2\u6570\nfunction processUser(int $userId): void {\n    \/\/ $userId\u306f\u5fc5\u305a\u6574\u6570\u578b\u3067\u3042\u308b\u3053\u3068\u304c\u4fdd\u8a3c\u3055\u308c\u3066\u3044\u308b\n    \/\/ \u95a2\u6570\u5185\u3067\u306fintval()\u306f\u4e0d\u8981\u306b\u306a\u308b\n    \n    $user = getUserById($userId);\n    \/\/ \u51e6\u7406\u3092\u7d9a\u884c...\n}\n\n\/\/ \u547c\u3073\u51fa\u3057\u5074\u3067\u306e\u578b\u5909\u63db\n$inputId = $_GET['user_id'] ?? '';\n\n\/\/ \u691c\u8a3c\u3057\u3066\u304b\u3089\u5909\u63db\nif (is_numeric($inputId)) {\n    processUser(intval($inputId)); \/\/ \u6574\u6570\u578b\u306b\u5909\u63db\u3057\u3066\u6e21\u3059\n} else {\n    \/\/ \u30a8\u30e9\u30fc\u51e6\u7406\n    echo \"\u6709\u52b9\u306a\u30e6\u30fc\u30b6\u30fcID\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044\";\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u30d1\u30bf\u30fc\u30f3\u306e\u30dd\u30a4\u30f3\u30c8\u306f\u3001<strong>\u5165\u529b\u5024\u306e\u691c\u8a3c\u3068\u578b\u5909\u63db\u3092\u547c\u3073\u51fa\u3057\u5074\u3067\u884c\u3044<\/strong>\u3001\u95a2\u6570\u5185\u3067\u306f\u578b\u304c\u4fdd\u8a3c\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u3092\u524d\u63d0\u306b\u3059\u308b\u3053\u3068\u3067\u3059\u3002\u3053\u3046\u3059\u308b\u3053\u3068\u3067\u3001\u95a2\u6570\u306e\u5b9f\u88c5\u304c\u30b7\u30f3\u30d7\u30eb\u306b\u306a\u308a\u3001\u610f\u56f3\u3057\u306a\u3044\u578b\u306e\u5024\u304c\u6df7\u5165\u3059\u308b\u30ea\u30b9\u30af\u3092\u6e1b\u3089\u305b\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>Union Types\u306e\u6d3b\u7528<\/strong><\/p>\n\n\n\n<p>PHP 8\u3067\u5c0e\u5165\u3055\u308c\u305fUnion Types\uff08\u8907\u5408\u578b\uff09\u3068<code>intval()<\/code>\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u67d4\u8edf\u306a\u578b\u51e6\u7406\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6574\u6570\u307e\u305f\u306f\u6587\u5b57\u5217\u3092\u53d7\u3051\u5165\u308c\u308b\u95a2\u6570\nfunction processIdentifier(int|string $identifier): void {\n    \/\/ $identifier\u306f\u6574\u6570\u307e\u305f\u306f\u6587\u5b57\u5217\u3067\u3042\u308b\u3053\u3068\u304c\u4fdd\u8a3c\u3055\u308c\u3066\u3044\u308b\n    \n    \/\/ \u5185\u90e8\u51e6\u7406\u306e\u305f\u3081\u306b\u6574\u6570\u306b\u7d71\u4e00\u3057\u305f\u3044\u5834\u5408\n    $numericId = is_int($identifier) ? $identifier : intval($identifier);\n    \n    \/\/ \u51e6\u7406\u3092\u7d9a\u884c...\n}\n\n\/\/ \u547c\u3073\u51fa\u3057\u4f8b\nprocessIdentifier(123);         \/\/ \u6574\u6570\u3092\u305d\u306e\u307e\u307e\u6e21\u3059\nprocessIdentifier(\"456\");       \/\/ \u6587\u5b57\u5217\u3092\u6e21\u3059\uff08\u5185\u90e8\u3067intval\u5909\u63db\uff09\nprocessIdentifier($_GET['id']); \/\/ \u5165\u529b\u5024\u3092\u76f4\u63a5\u6e21\u305b\u308b\uff08\u6587\u5b57\u5217\u3068\u3057\u3066\uff09\n<\/pre>\n\n\n\n<p><strong>\u540d\u524d\u4ed8\u304d\u5f15\u6570\u3068\u306e\u9023\u643a<\/strong><\/p>\n\n\n\n<p>PHP 8\u306e\u540d\u524d\u4ed8\u304d\u5f15\u6570\u3092\u4f7f\u3046\u3068\u3001\u7279\u306b<code>intval()<\/code>\u306e\u57fa\u6570\u6307\u5b9a\u304c\u8aad\u307f\u3084\u3059\u304f\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u5f93\u6765\u306e\u547c\u3073\u51fa\u3057\u65b9\n$decimal = intval(\"FF\", 16); \/\/ \u7b2c2\u5f15\u6570\u306e\u610f\u5473\u304c\u5206\u304b\u308a\u306b\u304f\u3044\n\n\/\/ PHP 8\u306e\u540d\u524d\u4ed8\u304d\u5f15\u6570\u3092\u4f7f\u7528\n$decimal = intval(value: \"FF\", base: 16); \/\/ \u3088\u308a\u660e\u78ba\n\n\/\/ \u4efb\u610f\u306e\u9806\u5e8f\u3067\u306e\u6307\u5b9a\u3082\u53ef\u80fd\n$decimal = intval(base: 16, value: \"FF\");\n<\/pre>\n\n\n\n<p><strong>\u53b3\u683c\u306a\u578b\u30c1\u30a7\u30c3\u30af\u306e\u305f\u3081\u306e\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570<\/strong><\/p>\n\n\n\n<p>PHP 8\u306e\u578b\u30b7\u30b9\u30c6\u30e0\u3092\u6d3b\u304b\u3057\u305f\u3001\u3088\u308a\u5805\u7262\u306a\u6574\u6570\u5909\u63db\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\u306e\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u5b89\u5168\u306b\u6574\u6570\u5024\u3092\u53d6\u5f97\u3059\u308b\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\n * \n * @param mixed $input \u5909\u63db\u3059\u308b\u5165\u529b\u5024\n * @param array&lt;string, int|null&gt; $options \u30aa\u30d7\u30b7\u30e7\u30f3\u8a2d\u5b9a\n * @return int|null \u5909\u63db\u3055\u308c\u305f\u6574\u6570\u307e\u305f\u306f\u7121\u52b9\u306a\u5834\u5408\u306fnull\n *\/\nfunction safeInt(mixed $input, array $options = []): ?int {\n    \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u30aa\u30d7\u30b7\u30e7\u30f3\n    $defaults = [\n        'min' =&gt; null,    \/\/ \u6700\u5c0f\u5024\n        'max' =&gt; null,    \/\/ \u6700\u5927\u5024\n        'default' =&gt; null \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\n    ];\n    $options = array_merge($defaults, $options);\n    \n    \/\/ null\u3084\u7a7a\u6587\u5b57\u306e\u5834\u5408\n    if ($input === null || $input === '') {\n        return $options['default'];\n    }\n    \n    \/\/ \u6570\u5024\u3068\u3057\u3066\u89e3\u91c8\u3067\u304d\u306a\u3044\u5834\u5408\n    if (!is_numeric($input)) {\n        return $options['default'];\n    }\n    \n    \/\/ \u6574\u6570\u306b\u5909\u63db\n    $value = intval($input);\n    \n    \/\/ \u6700\u5c0f\u5024\u30c1\u30a7\u30c3\u30af\n    if ($options['min'] !== null &amp;&amp; $value &lt; $options['min']) {\n        return $options['min'];\n    }\n    \n    \/\/ \u6700\u5927\u5024\u30c1\u30a7\u30c3\u30af\n    if ($options['max'] !== null &amp;&amp; $value &gt; $options['max']) {\n        return $options['max'];\n    }\n    \n    return $value;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\n$page = safeInt($_GET['page'] ?? null, [\n    'min' =&gt; 1,\n    'default' =&gt; 1\n]);\n\n$limit = safeInt($_GET['limit'] ?? null, [\n    'min' =&gt; 1,\n    'max' =&gt; 100,\n    'default' =&gt; 20\n]);\n<\/pre>\n\n\n\n<p><strong>\u5217\u6319\u578b\uff08Enum\uff09\u3068\u306e\u9023\u643a\uff08PHP 8.1\u4ee5\u964d\uff09<\/strong><\/p>\n\n\n\n<p>PHP 8.1\u3067\u5c0e\u5165\u3055\u308c\u305f\u5217\u6319\u578b\uff08Enum\uff09\u3068<code>intval()<\/code>\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3068\u3001\u3088\u308a\u578b\u5b89\u5168\u306a\u30b3\u30fc\u30c9\u304c\u66f8\u3051\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6574\u6570\u5024\u3092\u6301\u3064\u5217\u6319\u578b\uff08PHP 8.1\u4ee5\u964d\uff09\nenum UserStatus: int {\n    case Active = 1;\n    case Inactive = 0;\n    case Suspended = 2;\n    \n    \/\/ \u6574\u6570\u5024\u304b\u3089\u5217\u6319\u578b\u3092\u53d6\u5f97\u3059\u308b\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u30e1\u30bd\u30c3\u30c9\n    public static function fromInt(int $value): ?self {\n        foreach (self::cases() as $case) {\n            if ($case-&gt;value === $value) {\n                return $case;\n            }\n        }\n        return null;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b - \u30e6\u30fc\u30b6\u30fc\u5165\u529b\u304b\u3089\u5b89\u5168\u306b\u5217\u6319\u578b\u3092\u53d6\u5f97\n$inputStatus = $_GET['status'] ?? null;\n$status = null;\n\nif (is_numeric($inputStatus)) {\n    $status = UserStatus::fromInt(intval($inputStatus));\n}\n\nif ($status === UserStatus::Active) {\n    \/\/ \u30a2\u30af\u30c6\u30a3\u30d6\u30e6\u30fc\u30b6\u30fc\u306e\u51e6\u7406\n} elseif ($status === UserStatus::Suspended) {\n    \/\/ \u505c\u6b62\u4e2d\u30e6\u30fc\u30b6\u30fc\u306e\u51e6\u7406\n} else {\n    \/\/ \u7121\u52b9\u306a\u30b9\u30c6\u30fc\u30bf\u30b9\u306e\u51e6\u7406\n}\n<\/pre>\n\n\n\n<p><strong>\u9759\u7684\u89e3\u6790\u30c4\u30fc\u30eb\u3068\u306e\u9023\u643a<\/strong><\/p>\n\n\n\n<p>PHP 8\u306e\u578b\u30b7\u30b9\u30c6\u30e0\u306f\u9759\u7684\u89e3\u6790\u30c4\u30fc\u30eb\u3068\u306e\u76f8\u6027\u304c\u826f\u304f\u3001<code>intval()<\/code>\u306e\u4f7f\u7528\u30d1\u30bf\u30fc\u30f3\u3082\u691c\u8a3c\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * @param string|int|null $input\n * @return positive-int User ID\n *\/\nfunction validateUserId(string|int|null $input): int {\n    if ($input === null || !is_numeric($input)) {\n        throw new InvalidArgumentException('\u7121\u52b9\u306a\u30e6\u30fc\u30b6\u30fcID');\n    }\n    \n    $id = intval($input);\n    \n    if ($id &lt;= 0) {\n        throw new InvalidArgumentException('\u30e6\u30fc\u30b6\u30fcID\u306f\u6b63\u306e\u6574\u6570\u3067\u3042\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059');\n    }\n    \n    return $id;\n}\n<\/pre>\n\n\n\n<p>\u3053\u306e\u30b3\u30fc\u30c9\u3092PHPStan\u3084Psalm\u306a\u3069\u306e\u9759\u7684\u89e3\u6790\u30c4\u30fc\u30eb\u3067\u691c\u8a3c\u3059\u308b\u3068\u3001\u623b\u308a\u5024\u306e\u578b\u304c\u300c\u6b63\u306e\u6574\u6570\u300d\u3067\u3042\u308b\u3053\u3068\u3092\u4fdd\u8a3c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p><strong>PHP 8\u6642\u4ee3\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5883\u754c\u3067\u306e\u691c\u8a3c\u3068\u5909\u63db<\/strong>: \u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u5883\u754c\uff08\u5165\u529b\u3092\u53d7\u3051\u53d6\u308b\u7b87\u6240\uff09\u3067\u9069\u5207\u306a\u691c\u8a3c\u3068\u578b\u5909\u63db\u3092\u884c\u3044\u3001\u5185\u90e8\u3067\u306f\u578b\u5ba3\u8a00\u306b\u983c\u308b<\/li>\n\n\n\n<li><strong>\u578b\u5ba3\u8a00\u306e\u6d3b\u7528<\/strong>: \u53ef\u80fd\u306a\u9650\u308a\u578b\u5ba3\u8a00\u3092\u4f7f\u7528\u3057\u3066\u3001\u95a2\u6570\u3084\u30e1\u30bd\u30c3\u30c9\u306e\u5165\u51fa\u529b\u578b\u3092\u660e\u78ba\u306b\u3059\u308b<\/li>\n\n\n\n<li><strong>\u660e\u793a\u7684\u306a\u5909\u63db<\/strong>: \u6697\u9ed9\u7684\u306a\u578b\u5909\u63db\u306b\u983c\u3089\u305a\u3001<code>intval()<\/code>\u3084<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u3067\u660e\u793a\u7684\u306b\u5909\u63db\u3059\u308b<\/li>\n\n\n\n<li><strong>\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\u306e\u4f5c\u6210<\/strong>: \u5171\u901a\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u30ed\u30b8\u30c3\u30af\u3092\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\u306b\u307e\u3068\u3081\u3066\u518d\u5229\u7528\u3059\u308b<\/li>\n<\/ol>\n\n\n\n<p>PHP 8\u306e\u578b\u30b7\u30b9\u30c6\u30e0\u3092\u6d3b\u7528\u3059\u308b\u3053\u3068\u3067\u3001<code>intval()<\/code>\u306e\u4f7f\u7528\u304c\u3088\u308a\u52b9\u679c\u7684\u306b\u306a\u308a\u3001\u578b\u306e\u5b89\u5168\u6027\u304c\u9ad8\u304f\u3001\u30d0\u30b0\u306e\u5c11\u306a\u3044\u30b3\u30fc\u30c9\u304c\u66f8\u3051\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002\u7279\u306b\u5165\u529b\u5024\u306e\u691c\u8a3c\u3068\u578b\u5909\u63db\u3092\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u5883\u754c\u3067\u884c\u3044\u3001\u5185\u90e8\u51e6\u7406\u3067\u306f\u578b\u5ba3\u8a00\u306b\u983c\u308b\u30a2\u30d7\u30ed\u30fc\u30c1\u306f\u3001\u30e2\u30c0\u30f3\u306aPHP\u958b\u767a\u306b\u304a\u3044\u3066\u975e\u5e38\u306b\u52b9\u679c\u7684\u3067\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-40\">\u307e\u3068\u3081\uff1a\u5b89\u5168\u3067\u52b9\u7387\u7684\u306aintval()\u306e\u4f7f\u3044\u65b9<\/h2>\n\n\n\n<p>\u3053\u3053\u307e\u3067<code>intval()<\/code>\u95a2\u6570\u306e\u57fa\u672c\u304b\u3089\u5fdc\u7528\u307e\u3067\u3001\u69d8\u3005\u306a\u5074\u9762\u3092\u8a73\u3057\u304f\u898b\u3066\u304d\u307e\u3057\u305f\u3002PHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u306b\u304a\u3044\u3066\u3001\u3053\u306e\u4e00\u898b\u30b7\u30f3\u30d7\u30eb\u306a\u95a2\u6570\u304c\u6301\u3064\u91cd\u8981\u6027\u3068\u5f71\u97ff\u529b\u306f\u60f3\u50cf\u4ee5\u4e0a\u306b\u5927\u304d\u3044\u3082\u306e\u3067\u3059\u3002\u6700\u5f8c\u306b\u3001\u5b89\u5168\u3067\u52b9\u7387\u7684\u306a<code>intval()<\/code>\u306e\u4f7f\u3044\u65b9\u3092\u7dcf\u62ec\u3057\u3001\u5b9f\u8df5\u7684\u306a\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u307e\u3068\u3081\u307e\u3059\u3002<\/p>\n\n\n\n<p><code>intval()<\/code>\u3092\u4f7f\u3044\u3053\u306a\u3059\u3053\u3068\u3067\u3001\u3088\u308a\u5805\u7262\u3067\u5b89\u5168\u306aPHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u958b\u767a\u3067\u304d\u308b\u3067\u3057\u3087\u3046\u3002\u7279\u306b\u5916\u90e8\u304b\u3089\u306e\u5165\u529b\u3092\u51e6\u7406\u3059\u308b\u5834\u5408\u3084\u3001\u8907\u96d1\u306a\u30c7\u30fc\u30bf\u5909\u63db\u3092\u884c\u3046\u5834\u5408\u306b\u3001\u3053\u306e\u95a2\u6570\u306e\u9069\u5207\u306a\u4f7f\u7528\u306f\u4e0d\u53ef\u6b20\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-41\">\u3053\u306e\u8a18\u4e8b\u3067\u5b66\u3093\u30607\u3064\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u5b9f\u8df5\u3059\u308b\u305f\u3081\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8<\/h3>\n\n\n\n<p>\u3053\u306e\u8a18\u4e8b\u3067\u89e3\u8aac\u3057\u3066\u304d\u305f\u5185\u5bb9\u3092\u5b9f\u8df5\u3057\u3084\u3059\u3044\u3088\u3046\u3001\u4e3b\u8981\u306a7\u3064\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8\u5f62\u5f0f\u306b\u307e\u3068\u3081\u307e\u3057\u305f\u3002\u3053\u308c\u3089\u306e\u30dd\u30a4\u30f3\u30c8\u3092\u610f\u8b58\u3059\u308b\u3053\u3068\u3067\u3001<code>intval()<\/code>\u95a2\u6570\u3092\u3088\u308a\u5b89\u5168\u304b\u3064\u52b9\u679c\u7684\u306b\u4f7f\u3044\u3053\u306a\u305b\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-42\">1. \u57fa\u672c\u7684\u306a\u578b\u5909\u63db\u30c6\u30af\u30cb\u30c3\u30af<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] \u30e6\u30fc\u30b6\u30fc\u5165\u529b\uff08GET\/POST\u30d1\u30e9\u30e1\u30fc\u30bf\uff09\u306f\u5fc5\u305a<code>intval()<\/code>\u3067\u6574\u6570\u306b\u5909\u63db\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u5909\u63db\u524d\u306b<code>is_numeric()<\/code>\u3067\u5165\u529b\u304c\u6570\u5024\u3068\u3057\u3066\u59a5\u5f53\u304b\u3092\u78ba\u8a8d\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u6587\u5b57\u5217\u304b\u3089\u6570\u5024\u3092\u62bd\u51fa\u3059\u308b\u969b\u306f\u3001\u5148\u982d\u304b\u3089\u306e\u89e3\u6790\u7279\u6027\u3092\u7406\u89e3\u3057\u3066\u4f7f\u7528\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u304c\u91cd\u8981\u306a\u5834\u9762\u3067\u306f<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u306e\u4f7f\u7528\u3082\u691c\u8a0e\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$page = is_numeric($_GET['page'] ?? '') ? intval($_GET['page']) : 1;\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-43\">2. \u57fa\u6570\u6307\u5b9a\u306b\u3088\u308b\u9ad8\u5ea6\u306a\u5909\u63db<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] 16\u9032\u6570\u3092\u6271\u3046\u969b\u306f<code>intval($hex, 16)<\/code>\u306e\u5f62\u5f0f\u3092\u4f7f\u7528\u3059\u308b<\/li>\n\n\n\n<li>[ ] 2\u9032\u6570\u30c7\u30fc\u30bf\u306f<code>intval($binary, 2)<\/code>\u306710\u9032\u6570\u306b\u5909\u63db\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u30ab\u30e9\u30fc\u30b3\u30fc\u30c9\u306f\u5206\u89e3\u3057\u3066\u304b\u3089\u5909\u63db\u3059\u308b\uff08\u4f8b\uff1a<code>#FF5733<\/code>\u2192<code>FF<\/code>,<code>57<\/code>,<code>33<\/code>\uff09<\/li>\n\n\n\n<li>[ ] \u57fa\u6570\u306f2\u301c36\u306e\u7bc4\u56f2\u3067\u9069\u5207\u306b\u6307\u5b9a\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$color = \"#FF5733\";\n$r = intval(substr($color, 1, 2), 16); \/\/ 255\n$g = intval(substr($color, 3, 2), 16); \/\/ 87\n$b = intval(substr($color, 5, 2), 16); \/\/ 51\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-44\">3. \u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u5f37\u5316\u306e\u305f\u3081\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u9023\u643a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] \u5165\u529b\u5024\u306e\u691c\u8a3c\u3068\u578b\u5909\u63db\u3092\u7d44\u307f\u5408\u308f\u305b\u308b<\/li>\n\n\n\n<li>[ ] SQL\u30af\u30a8\u30ea\u3067\u306f\u30d7\u30ea\u30da\u30a2\u30fc\u30c9\u30b9\u30c6\u30fc\u30c8\u30e1\u30f3\u30c8\u3068\u7d44\u307f\u5408\u308f\u305b\u3066\u4f7f\u7528\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u5909\u63db\u5f8c\u306e\u5024\u304c\u6709\u52b9\u306a\u7bc4\u56f2\u5185\u306b\u3042\u308b\u304b\u3092\u691c\u8a3c\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u4e0d\u6b63\u306a\u5165\u529b\u306b\u5bfe\u3059\u308b\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u3092\u5b9f\u88c5\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$id = intval($_GET['id'] ?? 0);\nif ($id &lt;= 0) {\n    \/\/ \u30a8\u30e9\u30fc\u51e6\u7406\n    exit('\u7121\u52b9\u306aID\u3067\u3059');\n}\n$stmt = $pdo-&gt;prepare(\"SELECT * FROM users WHERE id = ?\");\n$stmt-&gt;execute([$id]);\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-45\">4. \u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u5bfe\u5fdc<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] NULL\u5024\u3084\u7a7a\u6587\u5b57\u5217\u3092\u9069\u5207\u306b\u51e6\u7406\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304c\u8aa4\u3063\u3066\u5165\u529b\u3055\u308c\u308b\u30b1\u30fc\u30b9\u306b\u5bfe\u5fdc\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u306e\u53ef\u80fd\u6027\u304c\u3042\u308b\u5927\u304d\u306a\u6570\u5024\u306b\u6ce8\u610f\u3059\u308b<\/li>\n\n\n\n<li>[ ] 32\u30d3\u30c3\u30c8\/64\u30d3\u30c3\u30c8\u74b0\u5883\u306e\u9055\u3044\u3092\u8003\u616e\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">function safeIntval($value, $default = 0) {\n    if ($value === null || $value === '' || is_array($value) || is_object($value)) {\n        return $default;\n    }\n    return intval($value);\n}\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-46\">5. \u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] \u540c\u3058\u5024\u306e\u7e70\u308a\u8fd4\u3057\u5909\u63db\u3092\u907f\u3051\u308b\uff08\u4e00\u5ea6\u5909\u63db\u3057\u305f\u5024\u3092\u5909\u6570\u306b\u4fdd\u5b58\uff09<\/li>\n\n\n\n<li>[ ] \u5927\u898f\u6a21\u30eb\u30fc\u30d7\u5185\u3067\u306f\u4e0d\u8981\u306a\u578b\u5909\u63db\u3092\u6e1b\u3089\u3059<\/li>\n\n\n\n<li>[ ] \u578b\u306e\u4e00\u8cab\u6027\u3092\u4fdd\u3063\u3066\u5909\u63db\u56de\u6570\u3092\u6700\u5c0f\u9650\u306b\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u5fc5\u8981\u306a\u5834\u6240\u3067\u306e\u307f<code>intval()<\/code>\u3092\u4f7f\u7528\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u6700\u9069\u5316\u524d\nforeach ($items as $item) {\n    if (intval($item['quantity']) &gt; 0) {\n        $total += intval($item['price']) * intval($item['quantity']);\n    }\n}\n\n\/\/ \u6700\u9069\u5316\u5f8c\nforeach ($items as $item) {\n    $quantity = intval($item['quantity']);\n    if ($quantity &gt; 0) {\n        $price = intval($item['price']);\n        $total += $price * $quantity;\n    }\n}\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-47\">6. \u56fd\u969b\u5316\u5bfe\u5fdc<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] \u5730\u57df\u56fa\u6709\u306e\u6570\u5024\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u3092\u8003\u616e\u3059\u308b\uff08\u4f8b\uff1a1.234,56 vs 1,234.56\uff09<\/li>\n\n\n\n<li>[ ] \u53ef\u80fd\u3067\u3042\u308c\u3070PHP intl\u62e1\u5f35\u3092\u6d3b\u7528\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u30ed\u30b1\u30fc\u30eb\u306b\u5fdc\u3058\u305f\u524d\u51e6\u7406\u3092\u5b9f\u88c5\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u56fd\u969b\u7684\u306a\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u306b\u5bfe\u5fdc\u3057\u305f\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u3092\u884c\u3046<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30c9\u30a4\u30c4\u5f0f\u6570\u5024\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\uff081.234,56\uff09\u3092\u51e6\u7406\nfunction parseGermanNumber($number) {\n    $normalized = str_replace('.', '', $number); \/\/ \u5343\u306e\u4f4d\u533a\u5207\u308a\u3092\u524a\u9664\n    $normalized = str_replace(',', '.', $normalized); \/\/ \u5c0f\u6570\u70b9\u3092\u5909\u63db\n    return intval($normalized);\n}\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-48\">7. PHP 8\u5bfe\u5fdc\u3068\u578b\u30b7\u30b9\u30c6\u30e0\u306e\u6d3b\u7528<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[ ] PHP 8\u306e\u578b\u5ba3\u8a00\u3092\u6d3b\u7528\u3057\u3066\u578b\u306e\u5b89\u5168\u6027\u3092\u9ad8\u3081\u308b<\/li>\n\n\n\n<li>[ ] Union Types\u3068\u7d44\u307f\u5408\u308f\u305b\u305f\u67d4\u8edf\u306a\u5b9f\u88c5\u3092\u691c\u8a0e\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u914d\u5217\u3084\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3059\u308b\u8b66\u544a\u306b\u5bfe\u5fdc\u3059\u308b<\/li>\n\n\n\n<li>[ ] \u53ef\u80fd\u3067\u3042\u308c\u3070\u9759\u7684\u89e3\u6790\u30c4\u30fc\u30eb\u3092\u6d3b\u7528\u3057\u3066\u578b\u306e\u554f\u984c\u3092\u65e9\u671f\u306b\u691c\u51fa\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p><strong>\u4f7f\u7528\u4f8b:<\/strong><\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ PHP 8\u306e\u578b\u5ba3\u8a00\u3092\u6d3b\u7528\nfunction processUser(int $userId): void {\n    \/\/ $userId\u306f\u5fc5\u305a\u6574\u6570\u578b\n    \/\/ \u51e6\u7406...\n}\n\n\/\/ \u547c\u3073\u51fa\u3057\u5074\u3067\u578b\u5909\u63db\n$input = $_GET['user_id'] ?? '';\nif (is_numeric($input)) {\n    processUser(intval($input));\n}\n<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8\u3092\u53c2\u8003\u306b\u3001\u81ea\u5206\u306e\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067<code>intval()<\/code>\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u6307\u91dd\u3068\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u7279\u306b\u5916\u90e8\u304b\u3089\u53d7\u3051\u53d6\u308b\u30c7\u30fc\u30bf\u306e\u51e6\u7406\u3084\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u304c\u91cd\u8981\u306a\u5834\u9762\u3067\u306f\u3001\u9069\u5207\u306a\u578b\u5909\u63db\u3068\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u306e\u7d44\u307f\u5408\u308f\u305b\u304c\u4e0d\u53ef\u6b20\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-49\">\u4eca\u65e5\u304b\u3089\u5c0e\u5165\u3067\u304d\u308bintval()\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h3>\n\n\n\n<p>\u3053\u3053\u3067\u306f\u3001\u660e\u65e5\u306e\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u304b\u3089\u3059\u3050\u306b\u53d6\u308a\u5165\u308c\u3089\u308c\u308b\u5b9f\u7528\u7684\u306a\u30d1\u30bf\u30fc\u30f3\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\u3084\u30d1\u30bf\u30fc\u30f3\u306f\u3001\u5b89\u5168\u6027\u3001\u4fdd\u5b88\u6027\u3001\u4f7f\u3044\u3084\u3059\u3055\u3092\u91cd\u8996\u3057\u3066\u8a2d\u8a08\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-50\">1. \u6c4e\u7528\u7684\u306a\u5b89\u5168\u6574\u6570\u5909\u63db\u95a2\u6570<\/h4>\n\n\n\n<p>\u3069\u3093\u306a\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u3082\u3059\u3050\u306b\u4f7f\u3048\u308b\u3001\u5b89\u5168\u306a\u6574\u6570\u5909\u63db\u95a2\u6570\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u3069\u3093\u306a\u5165\u529b\u5024\u3082\u5b89\u5168\u306b\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u95a2\u6570\n * \n * @param mixed $value \u5909\u63db\u3059\u308b\u5024\n * @param int $default \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\uff08\u5909\u63db\u3067\u304d\u306a\u3044\u5834\u5408\uff09\n * @return int \u5909\u63db\u3055\u308c\u305f\u6574\u6570\n *\/\nfunction safeInt($value, $default = 0) {\n    \/\/ null\u3001\u7a7a\u6587\u5b57\u3001\u914d\u5217\u3001\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u8fd4\u3059\n    if ($value === null || $value === '' || is_array($value) || is_object($value)) {\n        return $default;\n    }\n    \n    \/\/ \u6570\u5024\u3067\u306a\u3044\u5834\u5408\u3082\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\n    if (!is_numeric($value)) {\n        return $default;\n    }\n    \n    return intval($value);\n}\n<\/pre>\n\n\n\n<p>\u4f7f\u7528\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$user_id = safeInt($_GET['user_id'] ?? null, 0);\n$page = safeInt($_GET['page'] ?? null, 1);\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-51\">2. \u7bc4\u56f2\u5236\u9650\u4ed8\u304d\u6574\u6570\u5909\u63db<\/h4>\n\n\n\n<p>\u5024\u306e\u7bc4\u56f2\u3082\u540c\u6642\u306b\u5236\u9650\u3067\u304d\u308b\u4fbf\u5229\u306a\u95a2\u6570\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u6307\u5b9a\u7bc4\u56f2\u5185\u306e\u6574\u6570\u306b\u5909\u63db\u3059\u308b\u95a2\u6570\n * \n * @param mixed $value \u5909\u63db\u3059\u308b\u5024\n * @param int $min \u6700\u5c0f\u5024\n * @param int $max \u6700\u5927\u5024\n * @param int $default \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\n * @return int \u5909\u63db\u3055\u308c\u305f\u6574\u6570\n *\/\nfunction intBetween($value, $min, $max, $default = null) {\n    \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u304c\u6307\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u5834\u5408\u306f\u6700\u5c0f\u5024\u3092\u4f7f\u7528\n    $default = $default ?? $min;\n    \n    \/\/ \u5b89\u5168\u306b\u6574\u6570\u5909\u63db\n    $int = safeInt($value, $default);\n    \n    \/\/ \u7bc4\u56f2\u5185\u306b\u53ce\u3081\u308b\n    return min(max($int, $min), $max);\n}\n<\/pre>\n\n\n\n<p>\u4f7f\u7528\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30da\u30fc\u30b8\u756a\u53f7\uff081\u301c100\u306e\u7bc4\u56f2\uff09\n$page = intBetween($_GET['page'] ?? 1, 1, 100);\n\n\/\/ \u5546\u54c1\u6570\u91cf\uff081\u301c10\u306e\u7bc4\u56f2\u3001\u7121\u52b9\u306a\u5834\u5408\u306f1\uff09\n$quantity = intBetween($_POST['quantity'] ?? '', 1, 10);\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-52\">3. \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u306e\u305f\u3081\u306e\u5b89\u5168\u306aID\u51e6\u7406<\/h4>\n\n\n\n<p>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u3067\u983b\u51fa\u3059\u308bID\u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u5b89\u5168\u306a\u51e6\u7406\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u7528\u306e\u5b89\u5168\u306aID\u5909\u63db\n * \n * @param mixed $id \u5909\u63db\u3059\u308bID\n * @return int|null \u6709\u52b9\u306aID\u307e\u305f\u306fnull\n *\/\nfunction validId($id) {\n    $id = safeInt($id, 0);\n    return $id &gt; 0 ? $id : null;\n}\n<\/pre>\n\n\n\n<p>\u4f7f\u7528\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$user_id = validId($_GET['user_id'] ?? null);\nif ($user_id === null) {\n    \/\/ \u30a8\u30e9\u30fc\u51e6\u7406\n    exit('\u7121\u52b9\u306a\u30e6\u30fc\u30b6\u30fcID\u3067\u3059');\n}\n\n$stmt = $pdo-&gt;prepare(\"SELECT * FROM users WHERE id = ?\");\n$stmt-&gt;execute([$user_id]);\n$user = $stmt-&gt;fetch(PDO::FETCH_ASSOC);\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-53\">4. \u30d5\u30a9\u30fc\u30e0\u691c\u8a3c\u3068\u6574\u6570\u5909\u63db\u306e\u7d71\u5408<\/h4>\n\n\n\n<p>\u30d5\u30a9\u30fc\u30e0\u5165\u529b\u306e\u691c\u8a3c\u3068\u578b\u5909\u63db\u3092\u7d71\u5408\u3057\u305f\u4fbf\u5229\u306a\u95a2\u6570\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * \u30d5\u30a9\u30fc\u30e0\u5165\u529b\u3092\u691c\u8a3c\u3057\u3066\u6574\u6570\u306b\u5909\u63db\n * \n * @param array $data \u30d5\u30a9\u30fc\u30e0\u30c7\u30fc\u30bf\n * @param string $field \u30d5\u30a3\u30fc\u30eb\u30c9\u540d\n * @param array $options \u30aa\u30d7\u30b7\u30e7\u30f3\n * @return array \u691c\u8a3c\u7d50\u679c\n *\/\nfunction validateInt($data, $field, array $options = []) {\n    \/\/ \u30c7\u30d5\u30a9\u30eb\u30c8\u30aa\u30d7\u30b7\u30e7\u30f3\n    $options = array_merge([\n        'required' =&gt; true,\n        'min' =&gt; null,\n        'max' =&gt; null,\n        'default' =&gt; null\n    ], $options);\n    \n    \/\/ \u30d5\u30a3\u30fc\u30eb\u30c9\u5024\u306e\u53d6\u5f97\n    $value = $data[$field] ?? null;\n    \n    \/\/ \u5fc5\u9808\u30c1\u30a7\u30c3\u30af\n    if ($options['required'] &amp;&amp; ($value === null || $value === '')) {\n        return [\n            'valid' =&gt; false,\n            'value' =&gt; $options['default'],\n            'error' =&gt; '\u3053\u306e\u9805\u76ee\u306f\u5fc5\u9808\u3067\u3059'\n        ];\n    }\n    \n    \/\/ \u6570\u5024\u5f62\u5f0f\u30c1\u30a7\u30c3\u30af\n    if ($value !== null &amp;&amp; $value !== '' &amp;&amp; !is_numeric($value)) {\n        return [\n            'valid' =&gt; false,\n            'value' =&gt; $options['default'],\n            'error' =&gt; '\u6570\u5024\u3092\u5165\u529b\u3057\u3066\u304f\u3060\u3055\u3044'\n        ];\n    }\n    \n    \/\/ \u6574\u6570\u5909\u63db\n    $int_value = safeInt($value, $options['default']);\n    \n    \/\/ \u6700\u5c0f\u5024\u30c1\u30a7\u30c3\u30af\n    if ($options['min'] !== null &amp;&amp; $int_value &lt; $options['min']) {\n        return [\n            'valid' =&gt; false,\n            'value' =&gt; $options['min'],\n            'error' =&gt; '\u6700\u5c0f\u5024\u306f' . $options['min'] . '\u3067\u3059'\n        ];\n    }\n    \n    \/\/ \u6700\u5927\u5024\u30c1\u30a7\u30c3\u30af\n    if ($options['max'] !== null &amp;&amp; $int_value &gt; $options['max']) {\n        return [\n            'valid' =&gt; false,\n            'value' =&gt; $options['max'],\n            'error' =&gt; '\u6700\u5927\u5024\u306f' . $options['max'] . '\u3067\u3059'\n        ];\n    }\n    \n    \/\/ \u691c\u8a3c\u6210\u529f\n    return [\n        'valid' =&gt; true,\n        'value' =&gt; $int_value,\n        'error' =&gt; null\n    ];\n}\n<\/pre>\n\n\n\n<p>\u4f7f\u7528\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">$result = validateInt($_POST, 'quantity', [\n    'min' =&gt; 1,\n    'max' =&gt; 10,\n    'default' =&gt; 1\n]);\n\nif ($result['valid']) {\n    \/\/ \u691c\u8a3c\u6210\u529f\n    $quantity = $result['value'];\n} else {\n    \/\/ \u691c\u8a3c\u5931\u6557\n    $error = $result['error'];\n}\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-54\">5. JSON\u30c7\u30fc\u30bf\u306e\u578b\u5909\u63db<\/h4>\n\n\n\n<p>API\u30ec\u30b9\u30dd\u30f3\u30b9\u3084JSON\u5165\u529b\u306e\u578b\u5909\u63db\u306b\u5f79\u7acb\u3064\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/**\n * JSON\u30c7\u30fc\u30bf\u306e\u578b\u5909\u63db\n * \n * @param array $data \u5909\u63db\u3059\u308bJSON\u30c7\u30fc\u30bf\n * @param array $schema \u578b\u30b9\u30ad\u30fc\u30de\n * @return array \u5909\u63db\u3055\u308c\u305f\u30c7\u30fc\u30bf\n *\/\nfunction convertJsonTypes($data, array $schema) {\n    $result = [];\n    \n    foreach ($schema as $field =&gt; $type) {\n        if (!isset($data[$field])) {\n            continue;\n        }\n        \n        $value = $data[$field];\n        \n        switch ($type) {\n            case 'int':\n                $result[$field] = safeInt($value);\n                break;\n            case 'float':\n                $result[$field] = floatval($value);\n                break;\n            case 'bool':\n                $result[$field] = (bool)$value;\n                break;\n            case 'string':\n                $result[$field] = (string)$value;\n                break;\n            case 'array&lt;int&gt;':\n                if (!is_array($value)) {\n                    $result[$field] = [];\n                } else {\n                    $result[$field] = array_map('safeInt', $value);\n                }\n                break;\n            default:\n                $result[$field] = $value;\n                break;\n        }\n    }\n    \n    return $result;\n}\n<\/pre>\n\n\n\n<p>\u4f7f\u7528\u4f8b\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u30b9\u30ad\u30fc\u30de\u5b9a\u7fa9\n$schema = [\n    'id' =&gt; 'int',\n    'name' =&gt; 'string',\n    'active' =&gt; 'bool',\n    'scores' =&gt; 'array&lt;int&gt;'\n];\n\n\/\/ API\u30ec\u30b9\u30dd\u30f3\u30b9\u3092\u5909\u63db\n$json = '{\"id\":\"1001\",\"name\":\"Product X\",\"active\":\"1\",\"scores\":[\"85\",\"92\",\"78\"]}';\n$data = json_decode($json, true);\n$typedData = convertJsonTypes($data, $schema);\n\n\/\/ \u7d50\u679c: ['id' =&gt; 1001, 'name' =&gt; 'Product X', 'active' =&gt; true, 'scores' =&gt; [85, 92, 78]]\n<\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-55\">\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u306e\u307e\u3068\u3081<\/h4>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5165\u53e3\u3067\u306e\u578b\u5909\u63db<\/strong>: \u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3078\u306e\u5165\u529b\uff08\u30ea\u30af\u30a8\u30b9\u30c8\u30d1\u30e9\u30e1\u30fc\u30bf\u3001API\u30c7\u30fc\u30bf\u306a\u3069\uff09\u306f\u3001\u3067\u304d\u308b\u3060\u3051\u65e9\u3044\u6bb5\u968e\u3067\u9069\u5207\u306a\u578b\u306b\u5909\u63db\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li><strong>\u30d8\u30eb\u30d1\u30fc\u95a2\u6570\u306e\u6d3b\u7528<\/strong>: \u7e70\u308a\u8fd4\u3057\u4f7f\u3046\u30d1\u30bf\u30fc\u30f3\u306f\u3001\u4e0a\u8a18\u306e\u3088\u3046\u306a\u30d8\u30eb\u30d1\u30fc\u95a2\u6570\u306b\u307e\u3068\u3081\u3066\u518d\u5229\u7528\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li><strong>\u30b3\u30f3\u30c6\u30ad\u30b9\u30c8\u8003\u616e<\/strong>: \u4f7f\u7528\u30b3\u30f3\u30c6\u30ad\u30b9\u30c8\u306b\u5fdc\u3058\u3066\u6700\u9069\u306a\u65b9\u6cd5\u3092\u9078\u3073\u307e\u3057\u3087\u3046\uff08\u4f8b\uff1a\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u304c\u91cd\u8981\u306a\u3089<code>(int)<\/code>\u30ad\u30e3\u30b9\u30c8\u3001\u57fa\u6570\u6307\u5b9a\u304c\u5fc5\u8981\u306a\u3089<code>intval()<\/code>\uff09\u3002<\/li>\n\n\n\n<li><strong>\u30a8\u30e9\u30fc\u51e6\u7406\u306e\u7d71\u5408<\/strong>: \u578b\u5909\u63db\u3068\u30a8\u30e9\u30fc\u51e6\u7406\u3092\u7dca\u5bc6\u306b\u7d71\u5408\u3057\u3001\u4e0d\u6b63\u306a\u5024\u306b\u5bfe\u3057\u3066\u4e00\u8cab\u3057\u305f\u5bfe\u5fdc\u3092\u884c\u3044\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li><strong>\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u306e\u660e\u793a<\/strong>: \u578b\u5909\u63db\u304c\u5931\u6557\u3057\u305f\u5834\u5408\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u3092\u5e38\u306b\u660e\u793a\u7684\u306b\u6307\u5b9a\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li><strong>PHP 8\u5bfe\u5fdc<\/strong>: PHP 8\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u578b\u5ba3\u8a00\u3084\u540d\u524d\u4ed8\u304d\u5f15\u6570\u306a\u3069\u306e\u65b0\u6a5f\u80fd\u3082\u6d3b\u7528\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n\n\n\n<li><strong>\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u610f\u8b58<\/strong>: \u7279\u306b\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3084\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u3067\u306f\u3001\u578b\u5909\u63db\u3068\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3092\u5e38\u306b\u610f\u8b58\u3057\u307e\u3057\u3087\u3046\u3002<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u8df5\u7684\u306a\u30b3\u30fc\u30c9\u30d1\u30bf\u30fc\u30f3\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u5c0e\u5165\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5b89\u5168\u3067\u4fdd\u5b88\u3057\u3084\u3059\u3044PHP\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u958b\u767a\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059\u3002\u7279\u306b\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u3084\u5916\u90e8\u30c7\u30fc\u30bf\u306e\u51e6\u7406\u3092\u884c\u3046\u969b\u306b\u306f\u3001\u9069\u5207\u306a\u578b\u5909\u63db\u304c\u4e0d\u53ef\u6b20\u3067\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Warning: Undefined array key &#8220;is_admin&#8221; in \/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/ &#8230; <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[63],"tags":[],"class_list":{"0":"post-3674","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-php-syntax","7":"nothumb"},"_links":{"self":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/3674","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3674"}],"version-history":[{"count":1,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/3674\/revisions"}],"predecessor-version":[{"id":3675,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/3674\/revisions\/3675"}],"wp:attachment":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3674"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3674"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3674"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}