【ul】
<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'
src='http://code.jquery.com/jquery-1.4.2.js'></script>
<script type='text/javascript'>
$(window).load(function(){
$('#item2').insertBefore('#item1');
});
</script>
</head>
<body>
<ul id="mylist">
<li id="item1">Item 1</li>
<li id="item2">Item 2</li>
<li id="item3">Item 3</li>
</ul>
</body>
</html>
