菜鸟教程在线编辑器

AI 编程工具
 
                <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
</head>
<body>

<h1>HTMLCollection 对象</h1>

<p>循环输出这个页面的所有标签：</p>

<script>
var x, i, l;
x = document.getElementsByTagName("*");
l = x.length;
for (i = 0; i < l; i++) {
  document.write(x[i].tagName + "<br>");
}
</script>

</body>
</html>
              