<!DOCTYPE html> <html> <style> .democlass { color: red; } </style> <body> <h1 class="democlass">Element 对象</h1> <h2>getAttributeNode() 方法</h2> <p>第一个 h1 元素的 class 属性节点的值是:</p> <p id="demo"></p> <script> const element = document.getElementsByTagName("H1")[0]; const attr = element.getAttributeNode("class"); document.getElementById("demo").innerHTML = attr.value; </script> </body> </html>