常用三级导航菜单
<!DOCTYPE html>
<html>
<head>
<title>页面中常见垂直三级导航（jquery)</title>
<meta charset="UTF-8">
<link rel="shortcut icon" href="static/images/logo.png" type="image/x-icon" />
<!-- <link rel="stylesheet" href="static/css/style.css" type="text/css"> -->
<link rel="stylesheet" type="text/css" href="static/font-awesome/css/font-awesome.min.css">
<style type="text/css">
*{margin: 0px;padding: 0px;}
ul{list-style: none;}
a{text-decoration: none;color: #fff;}
.nav{width: 150px;height: 700px;background: #323232;margin-top: 10px;margin-left: 100px;}
.nav .one{height: 45px;line-height: 45px;text-align: center;border-bottom: 1px solid #5a5a5a;position: relative;}
.nav .one i{float: right;margin-right:8px;margin-top: 15px;}
.nav .one:hover{background:#be1616; }
.nav .one ul{position: absolute;left:150px;top:-1px;border-left: 1px solid #5a5a5a;border-right: 1px solid #5a5a5a; }
.two{width: 150px;height: 45px;line-height: 45px;float: left;text-align: center;border-bottom: 1px solid #5a5a5a;background: #323232;color: #fff;}
.two:hover{background:#be1616; }
.three{width:300px;color: #fff;background: #323232;padding: 10px 20px;position: absolute;left:151px;top: 0px; }
p{text-indent: 2em;line-height: 20px;text-align: left;}
</style>
<script src="static/js/jquery.js"></script>
<script >
$(function() {
$('.two,.three').hide()
$('li.one:eq(1)').mouseover(function(){
$(this).find(".two").slideDown(300)
})
$('li.one:eq(1)').mouseleave(function(){
$(this).find(".two").hide(300)
})
$('li.two').mouseover(function(){
$(this).find(".three").slideDown(300)
})
$('li.two').mouseleave(function(){
$(this).find(".three").hide()
})
})
</script>
</head>
<body>
<ul class="nav">
<li class="one" style="background: #be1616;"><a href="" style="margin-right: 10px;">上网</a></li>
<li class="one"><a href="">图书 <i class="fa fa-angle-right"></i></a>
<ul>
<li class="two" style="border-top: 1px solid #5a5a5a;">PHP手册<i class="fa fa-angle-right"></i>
<div class="three">
<p>《PHP手册》讲的是PHP的故事。</p>
</div>
</li>
<li class="two">大王饶命<i class="fa fa-angle-right"></i>
<div class="three">
<p>《大王饶命》讲的是贱圣的故事。</p>
</div></li>
<li class="two">JaveScript教程<i class="fa fa-angle-right"></i>
<div class="three">
<p>《JaveScript教程》讲的是JavaScript的故事。</p>
</div></li>
</li>
<li class="two">ECMAScript6入门<i class="fa fa-angle-right"></i>
<div class="three">
<p>《ECMAScript6入门》讲的还是JavaScript的故事。</p>
</div></li>
</li>
</ul>
</li>
<li class="one"><a href="">音乐 <i class="fa fa-angle-right"></i></a></li>
<li class="one"><a href="">视频 <i class="fa fa-angle-right"></i></a></li>
</ul>
</body>
</html>```
$(function() {
$('.two,.three').hide()
$('li.one:eq(1)').mouseover(function(){
//移上一级有二级弹
$(this).find(".two").slideDown(300)
})
$('li.one:eq(1)').mouseleave(function(){
$(this).find(".two").hide(300)
})
$('li.two').mouseover(function(){
//移上二级有三级弹
$(this).find(".three").slideDown(300)
})
$('li.two').mouseleave(function(){
$(this).find(".three").hide()
})
})
```