<html>
<body>
<h1 id="myH1" class="democlass">Element 对象</h1>
<h2>getAttribute() 方法</h2>
<p>h1 元素的 class 属性的值是:</p>
<p id="demo"></p>
<script>
const element = document.getElementById("myH1");
let text = element.getAttribute("class");
document.getElementById("demo").innerHTML = text;
</script>
</body>
</html>