<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JavaScript菜单侧边展开(改良版)</title>
</head>
<body>
<ul id="navigation">
<li><a href="#">系统管理</a>
<ul>
<li><a href="#">地区设置</a></li>
<li><a href="#">分行设置</a></li>
<li><a href="#">银行操作用户设置</a></li>
<li><a href="#">密码修改</a></li>
</ul>
</li>
<li><a href="#">学校管理</a>
<ul>
<li><a href="#">学校设置</a></li>
<li><a href="#">学校查询</a></li>
</ul>
</li>
<li><a href="#">基础信息管理</a></li>
<li><a href="#">统计系统查询</a></li>
</ul>
<script src="jquery-1.11.1.js"></script>
<script>
var $j = jQuery.noConflict();
$j(function(){
var lis = document.getElementById("navigation").getElementsByTagName("li");
for (var i=0; i<lis.length; i++) {
lis[i].onmouseover=function() {
var subMenu = this.getElementsByTagName("ul")[0];
subMenu.style.display = "block";
var subcolor = this.getElementsByTagName("a")[0];
subcolor.style.background = "lightblue";
}
lis[i].onmouseout=function() {
var subMenu = this.getElementsByTagName("ul")[0];
subMenu.style.display = "none";
var subcolor = this.getElementsByTagName("a")[0];
subcolor.style.background = "";
}
}
});
</script>
<script src="jquery-1.11.1.js"></script>
</body>
</html>原文：http://blog.csdn.net/sunflowerfiona/article/details/51331042
