菜鸟教程在线编辑器

 
                <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
<script>
function changeTabIndex()
{
	document.getElementById('1').tabIndex="3"
	document.getElementById('2').tabIndex="2"
	document.getElementById('3').tabIndex="1"
}
</script>
</head>
<body>

<p><a id="1" href="https://www.runoob.com">1</a></p>
<p><a id="2" href="https://www.runoob.com">2</a></p>
<p><a id="3" href="https://www.runoob.com">3</a></p>

<input type="button" onclick="changeTabIndex()"
value="Change TabIndex">

</body>
</html>
              