代码示例:(标识:jsck_document_documentelement)
<!DOCTYPE html>
<html>
<body>

<h1>Document 对象</h1>

<h2>documentElement 属性</h2>

<p>元素节点是:</p>

<p id="demo"></p>

<script>
document.getElementById("demo").innerHTML = document.documentElement.nodeName;
</script>

</body>
</html>
运行结果: