{"id":304831,"date":"2024-05-20T19:31:37","date_gmt":"2024-05-20T11:31:37","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/304831.html"},"modified":"2024-05-20T19:32:04","modified_gmt":"2024-05-20T11:32:04","slug":"%e5%89%8d%e7%ab%af-js-%e7%bc%96%e7%a8%8b%e4%b8%ad%e5%a6%82%e4%bd%95%e8%8e%b7%e5%8f%96-html-%e7%9a%84-dom-%e8%8a%82%e7%82%b9","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/304831.html","title":{"rendered":"\u524d\u7aef js \u7f16\u7a0b\u4e2d\u5982\u4f55\u83b7\u53d6 HTML \u7684 DOM \u8282\u70b9"},"content":{"rendered":"

\"\u524d\u7aef<\/p>\n

\u5728\u524d\u7aefJS\u7f16\u7a0b\u4e2d\uff0c\u83b7\u53d6HTML\u7684DOM\u8282\u70b9\u53ef\u4ee5\u901a\u8fc7\u591a\u79cd\u65b9\u6cd5\u5b9e\u73b0\uff0c\u4f8b\u5982\uff1adocument.getElementById<\/strong>\u3001document.getElementsByTagName<\/strong>\u3001document.querySelector<\/strong>\u3001document.querySelectorAll<\/strong> \u7b49\u3002\u5177\u4f53\u4f7f\u7528\u54ea\u4e00\u79cd\u65b9\u6cd5\u53d6\u51b3\u4e8e\u9700\u8981\u83b7\u53d6\u7684DOM\u5143\u7d20\u7684\u7279\u5b9a\u6761\u4ef6\u548c\u9009\u62e9\u5668\u3002\u4f8b\u5982\uff0c\u5f53\u4f60\u9700\u8981\u6309\u7167ID\u83b7\u53d6\u5355\u4e00\u5143\u7d20\u65f6\uff0cdocument.getElementById<\/strong> \u662f\u6700\u76f4\u63a5\u7684\u9009\u62e9\u3002<\/p>\n<\/p>\n

document.getElementById<\/strong> \u662f\u6700\u5e38\u7528\u4e14\u9ad8\u6548\u7684\u65b9\u6cd5\u4e4b\u4e00\uff0c\u5b83\u901a\u8fc7\u5143\u7d20\u7684ID\u76f4\u63a5\u8fd4\u56de\u5355\u4e2aDOM\u8282\u70b9\u3002\u8fd9\u4e2a\u65b9\u6cd5\u7684\u7279\u70b9\u662f\u53ea\u8fd4\u56de\u7b2c\u4e00\u4e2a\u5339\u914d\u7684\u5143\u7d20\uff0c\u56e0\u4e3a\u5728\u4e00\u4e2a\u5408\u6cd5\u7684HTML\u6587\u6863\u4e2d\uff0cID\u5e94\u662f\u552f\u4e00\u7684\u3002<\/p>\n<\/p>\n

\u4e00\u3001DOCUMENT.GETELEMENTBYID<\/h3>\n<\/p>\n

document.getElementById<\/strong> \u65b9\u6cd5\u662f\u83b7\u53d6\u5143\u7d20\u6700\u5feb\u901f\u7b80\u4fbf\u7684\u65b9\u6cd5\u3002\u5f53\u5f00\u53d1\u8005\u77e5\u9053\u6240\u9700\u5143\u7d20\u7684ID\u65f6\uff0c\u53ea\u9700\u8c03\u7528\u6b64\u65b9\u6cd5\u5e76\u4f20\u9012ID\u4f5c\u4e3a\u53c2\u6570\uff0c\u5c31\u80fd\u5f97\u5230\u5bf9\u5e94\u7684DOM\u5143\u7d20\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n

var element = document.getElementById('example-id');<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u884c\u4ee3\u7801\u4f1a\u5bfb\u627e\u5e76\u8fd4\u56deID\u4e3a"example-id"\u7684HTML\u5143\u7d20\u3002\u5982\u679c\u6ca1\u6709\u5143\u7d20\u4e0e\u63d0\u4f9b\u7684ID\u76f8\u7b26\uff0c\u8be5\u65b9\u6cd5\u5c06\u8fd4\u56denull\u3002<\/p>\n<\/p>\n
\u4e8c\u3001DOCUMENT.GETELEMENTSBYTAGNAME<\/h3>\n<\/p>\n
document.getElementsByTagName<\/strong> \u65b9\u6cd5\u5141\u8bb8\u901a\u8fc7\u6307\u5b9a\u7684\u6807\u7b7e\u540d\u6765\u83b7\u53d6\u4e00\u7ec4DOM\u5143\u7d20\u3002\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u7c7b\u6570\u7ec4\u5bf9\u8c61\uff08HTMLCollection\uff09\uff0c\u5176\u4e2d\u5305\u542b\u4e86\u6240\u6709\u7b26\u5408\u6761\u4ef6\u7684\u5143\u7d20\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
var elements = document.getElementsByTagName('div');<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u884c\u4ee3\u7801\u8fd4\u56de\u4e86\u9875\u9762\u4e2d\u6240\u6709div\u6807\u7b7e\u7684\u96c6\u5408\u3002\u5982\u679c\u6ca1\u6709\u627e\u5230\u76f8\u5e94\u7684\u5143\u6807\u7b7e\uff0c\u8be5\u65b9\u6cd5\u5c06\u8fd4\u56de\u7a7a\u7684HTMLCollection\u3002<\/p>\n<\/p>\n
\u4e09\u3001DOCUMENT.QUERYSELECTOR<\/h3>\n<\/p>\n
document.querySelector<\/strong> \u65b9\u6cd5\u5141\u8bb8\u4f60\u4f7f\u7528CSS\u9009\u62e9\u5668\u6765\u83b7\u53d6\u5355\u4e2aDOM\u8282\u70b9\u3002\u5b83\u8fd4\u56de\u6587\u6863\u4e2d\u5339\u914d\u6307\u5b9aCSS\u9009\u62e9\u5668\u7684\u7b2c\u4e00\u4e2a\u5143\u7d20\u3002\u5982\u679c\u6ca1\u6709\u627e\u5230\u5339\u914d\u7684\u5143\u7d20\uff0c\u5219\u8fd4\u56denull\u3002\u4ee3\u7801\u793a\u4f8b\uff1a<\/p>\n<\/p>\n
var element = document.querySelector('.class-name');<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u6b64\u4ee3\u7801\u4f1a\u8fd4\u56de\u6587\u6863\u4e2d\u62e5\u6709'class-name'\u8fd9\u4e2aCSS\u7c7b\u7684\u7b2c\u4e00\u4e2a\u5143\u7d20\u3002<\/p>\n<\/p>\n
\u56db\u3001DOCUMENT.QUERYSELECTORALL<\/h3>\n<\/p>\n
\u4e0edocument.querySelector<\/strong> \u76f8\u4f3c\uff0cdocument.querySelectorAll<\/strong> \u65b9\u6cd5\u4e5f\u4f7f\u7528CSS\u9009\u62e9\u5668\uff0c\u4f46\u662f\u5b83\u8fd4\u56de\u6240\u6709\u5339\u914d\u9009\u62e9\u5668\u7684\u5143\u7d20\u96c6\u5408\uff08NodeList\uff09\u800c\u4e0d\u4ec5\u4ec5\u662f\u7b2c\u4e00\u4e2a\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
var elements = document.querySelectorAll('.class-name');<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u884c\u4ee3\u7801\u5c06\u8fd4\u56de\u6587\u6863\u4e2d\u6240\u6709\u5177\u6709'class-name'\u7c7b\u7684\u5143\u7d20\u7684\u96c6\u5408\u3002<\/p>\n<\/p>\n
\u4e94\u3001\u8fdb\u9636\u9009\u62e9\u4e0e\u83b7\u53d6<\/h3>\n<\/p>\n
\u9664\u4e86\u4ee5\u4e0a\u8fd9\u4e9b\u5e38\u89c1\u7684\u83b7\u53d6DOM\u8282\u70b9\u7684\u65b9\u6cd5\u5916\uff0c\u8fd8\u6709\u4e00\u4e9b\u5176\u4ed6\u7684\u6280\u5de7\u53ef\u4ee5\u5728\u7279\u5b9a\u7684\u60c5\u51b5\u4e0b\u66f4\u6709\u6548\u7684\u83b7\u53d6DOM\u8282\u70b9\u3002<\/p>\n<\/p>\n
    \n
  1. \n
    \u83b7\u53d6\u7279\u5b9a\u4e0a\u4e0b\u6587\u4e2d\u7684\u5143\u7d20<\/strong>\uff1a<\/p>\n
     \u6709\u65f6\u4f60\u53ef\u80fd\u9700\u8981\u5728\u67d0\u4e2a\u7236\u5143\u7d20\u7684\u4e0a\u4e0b\u6587\u4e2d\u67e5\u627e\u5b50\u5143\u7d20\uff0c\u6b64\u65f6\u53ef\u4ee5\u4f7f\u7528parentNode.querySelectorAll<\/code>\u8fd9\u7c7b\u65b9\u6cd5\u3002<\/p>\n<\/p>\n<\/li>\n
  2. \n
    \u4f7f\u7528\u5c5e\u6027\u9009\u62e9\u5668<\/strong>\uff1a<\/p>\n
     \u5982\u679c\u5143\u7d20\u6ca1\u6709ID\u6216\u7c7b\uff0c\u4f46\u6709\u5176\u4ed6\u5c5e\u6027\uff08\u5982name<\/code>\u3001data-*<\/code>\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u5c5e\u6027\u9009\u62e9\u5668\uff0c\u5982\uff1a<\/p>\n<\/p>\n
    var elements = document.querySelectorAll('[data-custom-attribute="value"]');<\/p>\n
    <\/code><\/pre>\n<\/p>\n<\/li>\n<\/ol>\n
    \u516d\u3001\u83b7\u53d6\u8868\u5355\u5143\u7d20<\/h3>\n<\/p>\n
    \u8868\u5355\u5143\u7d20\u7684\u83b7\u53d6\u4e5f\u6709\u7279\u5b9a\u7684\u65b9\u6cd5\uff0c\u5982\u4f7f\u7528document.forms<\/code>\u96c6\u5408\uff0c\u7136\u540e\u53ef\u4ee5\u4f7f\u7528\u5143\u7d20\u7684name<\/code>\u6765\u83b7\u53d6\u7279\u5b9a\u7684\u8868\u5355\u63a7\u4ef6\u3002<\/p>\n<\/p>\n
    var form = document.forms['myForm'];<\/p>\n
    var input = form.elements['inputName'];<\/p>\n
    <\/code><\/pre>\n<\/p>\n
    \u4e03\u3001\u4f7f\u7528ID\u6216\u7c7b\u540d\u7279\u5b9a\u7684\u65b9\u6cd5<\/h3>\n<\/p>\n
    \u9664\u4e86\u4e0a\u8ff0\u7684\u901a\u7528\u65b9\u6cd5\uff0c\u90e8\u5206\u73b0\u4ee3\u7684\u6846\u67b6\u548c\u5e93\u53ef\u80fd\u63d0\u4f9b\u4e86\u7528\u4e8e\u83b7\u53d6DOM\u7684\u7279\u6b8a\u65b9\u6cd5\u6216\u8005\u8bed\u6cd5\u7cd6\u3002\u5176\u4e2d\u8457\u540d\u7684\u4f8b\u5b50\u5c31\u662fjQuery\uff0c\u5b83\u4f7f\u7528$<\/code>\u7b26\u53f7\u4f5c\u4e3a\u9009\u62e9\u5668\uff0c\u53ef\u4ee5\u975e\u5e38\u65b9\u4fbf\u5730\u64cd\u4f5cDOM\uff1a<\/p>\n<\/p>\n
    var element = $('#example-id'); \/\/ Get element by ID with jQuery<\/p>\n
    var elements = $('.class-name'); \/\/ Get elements by class name with jQuery<\/p>\n
    <\/code><\/pre>\n<\/p>\n
    \u5c3d\u7ba1\u539f\u751f\u7684JavaScript\u5df2\u7ecf\u63d0\u4f9b\u4e86\u4e30\u5bcc\u7684DOM\u64cd\u4f5c\u80fd\u529b\uff0c\u4e86\u89e3\u8fd9\u4e9b\u6846\u67b6\u548c\u5e93\u63d0\u4f9b\u7684\u4fbf\u5229\u6027\u4e5f\u5bf9\u5f00\u53d1\u8005\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n<\/p>\n
    \u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
    \u5982\u4f55\u5728\u524d\u7aef JavaScript \u7f16\u7a0b\u4e2d\u83b7\u53d6 HTML \u5143\u7d20\u7684 DOM \u8282\u70b9\uff1f<\/strong><\/p>\n
      \n
    1. \u4f7f\u7528 getElementById \u65b9\u6cd5\u83b7\u53d6\u6307\u5b9a id \u7684\u8282\u70b9<\/strong>
      \n\u60a8\u53ef\u4ee5\u4f7f\u7528 document.getElementById<\/code> \u65b9\u6cd5\uff0c\u901a\u8fc7\u4f20\u5165\u8282\u70b9\u7684 id \u5c5e\u6027\u7684\u503c\u6765\u83b7\u53d6\u5bf9\u5e94\u7684\u8282\u70b9\u3002\u4f8b\u5982\uff0c\u8981\u83b7\u53d6 id \u4e3a "myElement" \u7684\u8282\u70b9\uff1a<\/li>\n<\/ol>\n
      var element = document.getElementById("myElement");\n<\/code><\/pre>\n
        \n
      1. \u4f7f\u7528 querySelector \u65b9\u6cd5\u9009\u62e9\u6307\u5b9a\u7684\u8282\u70b9<\/strong>
        \n\u5982\u679c\u60a8\u9700\u8981\u9009\u62e9\u4e00\u4e2a\u5177\u6709\u7279\u5b9a\u7c7b\u540d\u3001\u6807\u7b7e\u540d\u6216\u5c5e\u6027\u7684\u8282\u70b9\uff0c\u53ef\u4ee5\u4f7f\u7528 document.querySelector<\/code> \u65b9\u6cd5\u3002\u4f8b\u5982\uff0c\u8981\u9009\u62e9\u5177\u6709\u7c7b\u540d "myClass" \u7684\u7b2c\u4e00\u4e2a\u8282\u70b9\uff1a<\/li>\n<\/ol>\n
        var element = document.querySelector(".myClass");\n<\/code><\/pre>\n
        \u8981\u9009\u62e9\u5177\u6709\u6807\u7b7e\u540d "h1" \u7684\u7b2c\u4e00\u4e2a\u8282\u70b9\uff1a<\/p>\n
        var element = document.querySelector("h1");\n<\/code><\/pre>\n
        \u8981\u9009\u62e9\u5177\u6709\u81ea\u5b9a\u4e49\u5c5e\u6027 "data-attribute" \u503c\u4e3a "test" \u7684\u7b2c\u4e00\u4e2a\u8282\u70b9\uff1a<\/p>\n
        var element = document.querySelector("[data-attribute='test']");\n<\/code><\/pre>\n
          \n
        1. \u4f7f\u7528 querySelectorAll \u65b9\u6cd5\u9009\u62e9\u591a\u4e2a\u8282\u70b9<\/strong>
          \n\u5982\u679c\u60a8\u9700\u8981\u9009\u62e9\u591a\u4e2a\u5177\u6709\u76f8\u540c\u7c7b\u540d\u3001\u6807\u7b7e\u540d\u6216\u5c5e\u6027\u7684\u8282\u70b9\uff0c\u53ef\u4ee5\u4f7f\u7528 document.querySelectorAll<\/code> \u65b9\u6cd5\u3002\u6b64\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a NodeList \u5bf9\u8c61\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u5176\u7d22\u5f15\u6765\u8bbf\u95ee\u6bcf\u4e2a\u8282\u70b9\u3002\u4f8b\u5982\uff0c\u8981\u9009\u62e9\u6240\u6709\u7c7b\u540d\u4e3a "myClass" \u7684\u8282\u70b9\uff1a<\/li>\n<\/ol>\n
          var elements = document.querySelectorAll(".myClass");\n<\/code><\/pre>\n
          \u8981\u9009\u62e9\u6240\u6709\u6807\u7b7e\u540d\u4e3a "p" \u7684\u8282\u70b9\uff1a<\/p>\n
          var elements = document.querySelectorAll("p");\n<\/code><\/pre>\n
          \u8981\u9009\u62e9\u6240\u6709\u5177\u6709\u81ea\u5b9a\u4e49\u5c5e\u6027 "data-attribute" \u7684\u8282\u70b9\uff1a<\/p>\n
          var elements = document.querySelectorAll("[data-attribute]");\n<\/code><\/pre>\n
          \u8fd9\u4e9b\u662f\u5728\u524d\u7aef JavaScript \u7f16\u7a0b\u4e2d\u83b7\u53d6 HTML DOM \u8282\u70b9\u7684\u5e38\u89c1\u65b9\u6cd5\u3002\u60a8\u53ef\u4ee5\u6839\u636e\u60a8\u7684\u9700\u6c42\u548c\u9875\u9762\u7684\u7ed3\u6784\u9009\u62e9\u9002\u5408\u7684\u65b9\u6cd5\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728\u524d\u7aefJS\u7f16\u7a0b\u4e2d\uff0c\u83b7\u53d6HTML\u7684DOM\u8282\u70b9\u53ef\u4ee5\u901a\u8fc7\u591a\u79cd\u65b9\u6cd5\u5b9e\u73b0\uff0c\u4f8b\u5982\uff1adocument.getElementB […]","protected":false},"author":3,"featured_media":304860,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/304831"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=304831"}],"version-history":[{"count":0,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/304831\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/304860"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=304831"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=304831"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=304831"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}