{"id":4498,"date":"2023-03-30T02:29:52","date_gmt":"2023-03-29T17:29:52","guid":{"rendered":"https:\/\/engineering.webstudio168.jp\/?p=4498"},"modified":"2023-04-14T11:03:49","modified_gmt":"2023-04-14T02:03:49","slug":"javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall","status":"publish","type":"post","link":"https:\/\/engineering.webstudio168.jp\/blog\/javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall\/","title":{"rendered":"\u3010JavaScirpt\u3011DOM\u8981\u7d20\u306e\u6307\u5b9a\u65b9\u6cd5\u307e\u3068\u3081"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_86 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u6b21<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/engineering.webstudio168.jp\/blog\/javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall\/#getElementById%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\" >getElementById()\u306b\u3064\u3044\u3066<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/engineering.webstudio168.jp\/blog\/javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall\/#getElementsByClassName%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\" >getElementsByClassName()\u306b\u3064\u3044\u3066<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/engineering.webstudio168.jp\/blog\/javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall\/#getElementsByTagName%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\" >getElementsByTagName()\u306b\u3064\u3044\u3066<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/engineering.webstudio168.jp\/blog\/javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall\/#querySelector%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\" >querySelector()\u306b\u3064\u3044\u3066<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/engineering.webstudio168.jp\/blog\/javascirptdom-getelementbyid-classname-tagname-queryselector-queryselectorall\/#querySelectorAll%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\" >querySelectorAll()\u306b\u3064\u3044\u3066<\/a><\/li><\/ul><\/nav><\/div>\n\n<p class=\"wp-block-paragraph\">JavaScript\u3067DOM\uff08<strong>D<\/strong>ocument <strong>O<\/strong>bject <strong>M<\/strong>odel\uff09\u8981\u7d20\u3092\u6307\u5b9a\u3059\u308b\u65b9\u6cd5\u306b\u306f\u3044\u304f\u3064\u304b\u3042\u308a\u307e\u3059\u304c\u3001\u4ee3\u8868\u7684\u306a\u65b9\u6cd5\u3092\u4ee5\u4e0b\u306b\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uff08\uff11\uff09<code>getElementById()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"getElementById.js\" data-lang=\"JavaScript\"><code>document.getElementById(&quot;\u8981\u7d20\u306eID&quot;)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u8981\u7d20\u306eID\u5c5e\u6027\u306b\u6307\u5b9a\u3055\u308c\u305f\u5024\u3092\u5f15\u6570\u306b\u6307\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001\u305d\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uff08\uff12\uff09<code>getElementsByClassName()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"getElementsByClassName.js\" data-lang=\"JavaScript\"><code>document.getElementsByClassName(&quot;\u30af\u30e9\u30b9\u540d&quot;)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u8981\u7d20\u306eclass\u5c5e\u6027\u306b\u6307\u5b9a\u3055\u308c\u305f\u5024\u3092\u5f15\u6570\u306b\u6307\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001\u305d\u306e\u30af\u30e9\u30b9\u306b\u5c5e\u3059\u308b\u8981\u7d20\u3092<strong>\u5168\u3066<\/strong>\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uff08\uff13\uff09<code>getElementsByTagName()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"getElementsByTagName.js\" data-lang=\"JavaScript\"><code>document.getElementsByTagName(&quot;\u30bf\u30b0\u540d&quot;)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u6307\u5b9a\u3055\u308c\u305f\u30bf\u30b0\u540d\u306b\u8a72\u5f53\u3059\u308b\u8981\u7d20\u3092<strong>\u5168\u3066<\/strong>\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uff08\uff14\uff09<code>querySelector()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"querySelector.js\" data-lang=\"JavaScript\"><code>document.querySelector(&quot;CSS\u30bb\u30ec\u30af\u30bf\u30fc&quot;)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">CSS\u30bb\u30ec\u30af\u30bf\u30fc\u3092\u6307\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001\u8a72\u5f53\u3059\u308b\u8981\u7d20\u306e\u3046\u3061<strong>\u6700\u521d\u306b\u30de\u30c3\u30c1\u3059\u308b\u8981\u7d20<\/strong>\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uff08\uff15\uff09<code>querySelectorAll()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"querySelectorAll.js\" data-lang=\"JavaScript\"><code>document.querySelectorAll(&quot;CSS\u30bb\u30ec\u30af\u30bf\u30fc&quot;)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">CSS\u30bb\u30ec\u30af\u30bf\u30fc\u3092\u6307\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001\u8a72\u5f53\u3059\u308b\u8981\u7d20<strong>\u5168\u3066<\/strong>\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u3089\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u9ad8\u5ea6\u306aDOM\u8981\u7d20\u306e\u6307\u5b9a\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"getElementById%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\"><\/span>getElementById()\u306b\u3064\u3044\u3066<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementById()<\/code>\u306f\u3001DOM(<strong>D<\/strong>ocument <strong>O<\/strong>bject <strong>M<\/strong>odel)\u3067ID\u5c5e\u6027\u306b\u3088\u3063\u3066\u6307\u5b9a\u3055\u308c\u305f\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u305f\u3081\u306eJavaScript\u306e\u30e1\u30bd\u30c3\u30c9\u3067\u3059\u3002\u3053\u306e\u30e1\u30bd\u30c3\u30c9\u306f\u3001document\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5c5e\u3059\u308b\u30e1\u30bd\u30c3\u30c9\u306e1\u3064\u3067\u3042\u308a\u3001HTML\u6587\u66f8\u5185\u306e\u4efb\u610f\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementById()<\/code>\u306e\u4f7f\u3044\u65b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"getElementById.js\" data-lang=\"JavaScript\"><code>document.getElementById(id);<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3053\u3067\u3001<code>id<\/code>\u306f\u691c\u7d22\u3059\u308b\u8981\u7d20\u306eID\u5c5e\u6027\u306e\u5024\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002\u6307\u5b9a\u3055\u308c\u305fID\u5c5e\u6027\u3092\u6301\u3064\u6700\u521d\u306e\u8981\u7d20\u304c\u8fd4\u3055\u308c\u307e\u3059\u3002<span class=\"marker-blue\">\u6307\u5b9a\u3055\u308c\u305fID\u5c5e\u6027\u3092\u6301\u3064\u8981\u7d20\u304c\u5b58\u5728\u3057\u306a\u3044\u5834\u5408\u306f\u3001null\u304c\u8fd4\u3055\u308c\u307e\u3059\u3002<\/span><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"getElementsByClassName%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\"><\/span>getElementsByClassName()\u306b\u3064\u3044\u3066<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementsByClassName()<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001DOM\u3067class\u5c5e\u6027\u306b\u3088\u3063\u3066\u6307\u5b9a\u3055\u308c\u305f\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u305f\u3081\u306e\u30e1\u30bd\u30c3\u30c9\u3067\u3059\u3002\u3053\u306e\u30e1\u30bd\u30c3\u30c9\u306f\u3001document\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5c5e\u3059\u308b\u30e1\u30bd\u30c3\u30c9\u306e1\u3064\u3067\u3042\u308a\u3001HTML\u6587\u66f8\u5185\u306e\u4efb\u610f\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementsByClassName()<\/code>\u306e\u4f7f\u3044\u65b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"getElementsByClassName.js\" data-lang=\"JavaScript\"><code>document.getElementsByClassName(className);<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3053\u3067\u3001<code>className<\/code>\u306f\u691c\u7d22\u3059\u308b\u8981\u7d20\u306eclass\u5c5e\u6027\u306e\u5024\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002\u6307\u5b9a\u3055\u308c\u305fclass\u5c5e\u6027\u3092\u6301\u3064<span class=\"marker-blue\">\u5168\u3066\u306e\u8981\u7d20\u304c\u53d6\u5f97\u3055\u308c\u307e\u3059<\/span>\uff08<code>getElementById<\/code>\u3068\u9055\u3063\u3066\u3001<code>getElement<\/code>\u300c<code>s<\/code>\u300d\u3067\u3059\u304b\u3089\u306d\uff01\uff09\u3002\u53d6\u5f97\u3055\u308c\u305f\u8981\u7d20\u306f\u3001HTML\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3068\u547c\u3070\u308c\u308b\u914d\u5217\u306e\u3088\u3046\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u683c\u7d0d\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306f\u3001\u4f8b\u3068\u3057\u3066HTML\u6587\u66f8\u5185\u306eclass\u5c5e\u6027\u304c&#8221;<code>myClass<\/code>&#8220;\u3067\u3042\u308b\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u65b9\u6cd5\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-html\" data-file=\"getElementsByClassName.html\" data-lang=\"HTML\"><code>&lt;div class=&quot;myClass&quot;&gt;Hello, World!&lt;\/div&gt;\n&lt;div class=&quot;myClass&quot;&gt;This is an example of getElementsByClassName method.&lt;\/div&gt;\n\n&lt;script&gt;\nvar elements = document.getElementsByClassName(&quot;myClass&quot;);\nconsole.log(elements);\n&lt;\/script&gt;<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u8a18\u306e\u4f8b\u3067\u306f\u3001<code>getElementsByClassName()<\/code>\u30e1\u30bd\u30c3\u30c9\u306b\u3088\u3063\u3066\u3001class\u5c5e\u6027\u304c&#8221;<code>myClass<\/code>&#8220;\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3057\u3066\u3044\u307e\u3059\u3002\u53d6\u5f97\u3057\u305f\u8981\u7d20\u306f\u3001\u5909\u6570&#8221;<code>elements<\/code>&#8220;\u306b\u4ee3\u5165\u3055\u308c\u3001\u305d\u306e\u5024\u304c<code>console.log<\/code>\u3067\u51fa\u529b\u3055\u308c\u307e\u3059\u3002\u53d6\u5f97\u3055\u308c\u305f\u8981\u7d20\u306f\u3001HTML\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306b\u683c\u7d0d\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001<span class=\"marker-blue\">\u30eb\u30fc\u30d7\u3092\u4f7f\u7528\u3057\u3066\u500b\u3005\u306e\u8981\u7d20\u306b\u30a2\u30af\u30bb\u30b9\u3059\u308b<\/span>\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementsByClassName()<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001\u8907\u6570\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u305f\u3081\u306e\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9\u3067\u3042\u308a\u3001JavaScript\u3067DOM\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u969b\u306b\u983b\u7e41\u306b\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002\u305f\u3060\u3057\u3001class\u5c5e\u6027\u304c\u91cd\u8907\u3057\u3066\u3044\u308b\u5834\u5408\u3001\u3053\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3057\u3066\u53d6\u5f97\u3057\u305f\u8981\u7d20\u306f\u3001HTML\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306b\u9806\u5e8f\u4ed8\u3051\u3089\u308c\u3066\u8fd4\u3055\u308c\u308b\u3053\u3068\u306b\u7559\u610f\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"getElementsByTagName%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\"><\/span>getElementsByTagName()\u306b\u3064\u3044\u3066<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementsByTagName()<\/code>\u306e\u4f7f\u3044\u65b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"getElementsByTagName.js\" data-lang=\"JavaScript\"><code>document.getElementsByTagName(tagName);<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3053\u3067\u3001<code>tagName<\/code>\u306f\u691c\u7d22\u3059\u308b\u8981\u7d20\u306e<strong>\u30bf\u30b0\u540d<\/strong>\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002<span class=\"marker-blue\">\u6307\u5b9a\u3055\u308c\u305f\u30bf\u30b0\u540d\u3092\u6301\u3064\u5168\u3066\u306e\u8981\u7d20\u304c\u53d6\u5f97\u3055\u308c\u307e\u3059<\/span>\u3002\u53d6\u5f97\u3055\u308c\u305f\u8981\u7d20\u306f\u3001HTML\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3068\u547c\u3070\u308c\u308b\u914d\u5217\u306e\u3088\u3046\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u683c\u7d0d\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306f\u3001\u4f8b\u3068\u3057\u3066HTML\u6587\u66f8\u5185\u306eh1\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u65b9\u6cd5\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-html\" data-file=\"getElementsByTagName.html\" data-lang=\"HTML\"><code>&lt;h1&gt;Heading 1&lt;\/h1&gt;\n&lt;p&gt;This is a paragraph.&lt;\/p&gt;\n\n&lt;script&gt;\nvar headings = document.getElementsByTagName(&quot;h1&quot;);\nconsole.log(headings);\n&lt;\/script&gt;<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u8a18\u306e\u4f8b\u3067\u306f\u3001<code>getElementsByTagName()<\/code>\u30e1\u30bd\u30c3\u30c9\u306b\u3088\u3063\u3066\u3001<code>h1<\/code>\u8981\u7d20\u3092\u53d6\u5f97\u3057\u3066\u3044\u307e\u3059\u3002\u53d6\u5f97\u3057\u305f\u8981\u7d20\u306f\u3001\u5909\u6570&#8221;<code>headings<\/code>&#8220;\u306b\u4ee3\u5165\u3055\u308c\u3001\u305d\u306e\u5024\u304c<code>console.log<\/code>\u3067\u51fa\u529b\u3055\u308c\u307e\u3059\u3002\u53d6\u5f97\u3055\u308c\u305f\u8981\u7d20\u306f\u3001HTML\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306b\u683c\u7d0d\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u30eb\u30fc\u30d7\u3092\u4f7f\u7528\u3057\u3066\u500b\u3005\u306e\u8981\u7d20\u306b\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><code>getElementsByTagName()<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001<span class=\"marker-blue\">\u8907\u6570\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b<\/span>\u305f\u3081\u306e\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9\u3067\u3042\u308a\u3001JavaScript\u3067DOM\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u969b\u306b\u983b\u7e41\u306b\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u540c\u3058\u30bf\u30b0\u540d\u3092\u6301\u3064\u8981\u7d20\u304c\u8907\u6570\u5b58\u5728\u3059\u308b\u5834\u5408\u3001\u3053\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3057\u3066\u53d6\u5f97\u3057\u305f\u8981\u7d20\u306f\u3001HTML\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306b\u9806\u5e8f\u4ed8\u3051\u3089\u308c\u3066\u8fd4\u3055\u308c\u308b\u3053\u3068\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"querySelector%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\"><\/span>querySelector()\u306b\u3064\u3044\u3066<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><code>querySelector()<\/code>\u306e\u4f7f\u3044\u65b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"querySelector.js\" data-lang=\"JavaScript\"><code>document.querySelector(selector);<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3053\u3067\u3001<code>selector<\/code>\u306fCSS\u30bb\u30ec\u30af\u30bf\u30fc\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002\u6307\u5b9a\u3055\u308c\u305f\u30bb\u30ec\u30af\u30bf\u30fc\u306b\u4e00\u81f4\u3059\u308b<span class=\"marker-blue\">\u6700\u521d\u306e\u8981\u7d20\u304c\u53d6\u5f97\u3055\u308c\u307e\u3059<\/span>\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306f\u3001\u4f8b\u3068\u3057\u3066HTML\u6587\u66f8\u5185\u306eid\u5c5e\u6027\u304c&#8221;<code>myElement<\/code>&#8220;\u3067\u3042\u308b\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u65b9\u6cd5\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-html\" data-file=\"querySelector.html\" data-lang=\"HTML\"><code>&lt;div id=&quot;myElement&quot;&gt;Hello, World!&lt;\/div&gt;\n&lt;div class=&quot;myClass&quot;&gt;This is an example of querySelector method.&lt;\/div&gt;\n\n&lt;script&gt;\nvar element = document.querySelector(&quot;#myElement&quot;);\nconsole.log(element);\n&lt;\/script&gt;<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u8a18\u306e\u4f8b\u3067\u306f\u3001<code>querySelector()<\/code>\u30e1\u30bd\u30c3\u30c9\u306b\u3088\u3063\u3066\u3001id\u5c5e\u6027\u304c&#8221;<code>myElement<\/code>&#8220;\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3057\u3066\u3044\u307e\u3059\u3002\u53d6\u5f97\u3057\u305f\u8981\u7d20\u306f\u3001\u5909\u6570&#8221;<code>element<\/code>&#8220;\u306b\u4ee3\u5165\u3055\u308c\u3001\u305d\u306e\u5024\u304c<code>console.log<\/code>\u3067\u51fa\u529b\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><code>querySelector()<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001CSS\u30bb\u30ec\u30af\u30bf\u30fc\u3092\u4f7f\u7528\u3059\u308b\u305f\u3081\u3001\u8981\u7d20\u3092\u3088\u308a\u67d4\u8edf\u306b\u691c\u7d22\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u305f\u3068\u3048\u3070\u3001class\u5c5e\u6027\u3001\u5c5e\u6027\u5024\u3001\u968e\u5c64\u69cb\u9020\u306a\u3069\u3092\u4f7f\u7528\u3057\u3066\u8981\u7d20\u3092\u6307\u5b9a\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u307e\u305f\u3001<code>querySelectorAll()<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u3068\u3001\u6307\u5b9a\u3055\u308c\u305fCSS\u30bb\u30ec\u30af\u30bf\u30fc\u306b\u4e00\u81f4\u3059\u308b\u5168\u3066\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"querySelectorAll%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6\"><\/span>querySelectorAll()\u306b\u3064\u3044\u3066<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><code>querySelectorAll()<\/code>\u30e1\u30bd\u30c3\u30c9\u306e\u4f7f\u3044\u65b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-js\" data-file=\"querySelectorAll.js\" data-lang=\"JavaScript\"><code>document.querySelectorAll(selector);<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3053\u3067\u3001<code>selector<\/code>\u306fCSS\u30bb\u30ec\u30af\u30bf\u30fc\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002\u6307\u5b9a\u3055\u308c\u305f\u30bb\u30ec\u30af\u30bf\u30fc\u306b\u4e00\u81f4\u3059\u308b<span class=\"marker-blue\">\u5168\u3066\u306e\u8981\u7d20\u304c\u53d6\u5f97\u3055\u308c\u307e\u3059<\/span>\u3002\u53d6\u5f97\u3055\u308c\u305f\u8981\u7d20\u306f\u3001<span class=\"marker-under-red\">NodeList\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u683c\u7d0d\u3055\u308c\u307e\u3059<\/span>\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306f\u3001\u4f8b\u3068\u3057\u3066HTML\u6587\u66f8\u5185\u306eclass\u5c5e\u6027\u304c&#8221;<code>myClass<\/code>&#8220;\u3067\u3042\u308b\u8981\u7d20\u3092\u53d6\u5f97\u3059\u308b\u65b9\u6cd5\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism undefined-numbers lang-html\" data-file=\"querySelectorAll.html\" data-lang=\"HTML\"><code>&lt;div class=&quot;myClass&quot;&gt;Hello, World!&lt;\/div&gt;\n&lt;p class=&quot;myClass&quot;&gt;This is an example of querySelectorAll method.&lt;\/p&gt;\n\n&lt;script&gt;\nvar elements = document.querySelectorAll(&quot;.myClass&quot;);\nconsole.log(elements);\n&lt;\/script&gt;<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u8a18\u306e\u4f8b\u3067\u306f\u3001<code>querySelectorAll()<\/code>\u30e1\u30bd\u30c3\u30c9\u306b\u3088\u3063\u3066\u3001class\u5c5e\u6027\u304c&#8221;<code>myClass<\/code>&#8220;\u306e\u8981\u7d20\u3092\u53d6\u5f97\u3057\u3066\u3044\u307e\u3059\u3002<span class=\"marker-under-red\">\u53d6\u5f97\u3057\u305f\u8981\u7d20\u306f\u3001NodeList\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u683c\u7d0d<\/span>\u3055\u308c\u3001\u5909\u6570&#8221;<code>elements<\/code>&#8220;\u306b\u4ee3\u5165\u3055\u308c\u307e\u3059\u3002\u305d\u306e\u5024\u304c<code>console.log<\/code>\u3067\u51fa\u529b\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><code>querySelectorAll()<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001CSS\u30bb\u30ec\u30af\u30bf\u30fc\u3092\u4f7f\u7528\u3059\u308b\u305f\u3081\u3001\u8981\u7d20\u3092\u3088\u308a\u67d4\u8edf\u306b\u691c\u7d22\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u307e\u305f\u3001\u53d6\u5f97\u3057\u305fNodeList\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092for\u30eb\u30fc\u30d7\u3067\u7e70\u308a\u8fd4\u3057\u3066\u3001\u500b\u3005\u306e\u8981\u7d20\u306b\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>JavaScript\u3067DOM\uff08Document Object Model\uff09\u8981\u7d20\u3092\u6307\u5b9a\u3059\u308b\u65b9\u6cd5\u306b\u306f\u3044\u304f\u3064\u304b\u3042\u308a\u307e\u3059\u304c\u3001\u4ee3\u8868\u7684\u306a\u65b9\u6cd5\u3092\u4ee5\u4e0b\u306b\u7d39\u4ecb\u3057\u307e\u3059\u3002 \uff08\uff11\uff09getElementById()\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5 \u8981\u7d20\u306eI [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":4515,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[55],"tags":[8,48],"class_list":["post-4498","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-javascript","tag-javascript","tag-48"],"_links":{"self":[{"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/posts\/4498","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/comments?post=4498"}],"version-history":[{"count":19,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/posts\/4498\/revisions"}],"predecessor-version":[{"id":5186,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/posts\/4498\/revisions\/5186"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/media\/4515"}],"wp:attachment":[{"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/media?parent=4498"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/categories?post=4498"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/engineering.webstudio168.jp\/blog\/wp-json\/wp\/v2\/tags?post=4498"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}