本文实例讲述了JavaScript+CSS实现仿天猫侧边网页菜单效果。分享给大家供大家参考。具体如下：
这是一款自己写的仿天猫的菜单效果，二级分类的功能已经实现，但没有美化，留着用的朋友自己完善吧，JS功能已经实现，鼠标移在主分类上，二级分类向右伸出展开，目前淘宝网、天猫购物、京东都在用的导航菜单特效，测试时候请先点击一下菜单，主菜单就显示出来了。
运行效果截图如下：
在线演示地址如下：
http://demo.jb51.net/js/2015/js-css-ftamil-web-menu-style-codes/
具体代码如下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>仿天猫侧边网页菜单</title> <style type="text/css"> *{margin:0; padding:0;} body{ font-size:14px; font-family:"宋体";} h1, h2, h3{ font-size:14px; font-weight:normal;} li{ list-style:none;} a{ color:#333; text-decoration:none;} #nav{ width:202px; height:35px; background:#C00; margin:50px 0 0 20px;} #nav h1{ padding-left:17px; line-height:35px; color:#fff; margin-right:17px;} #box{ width:200px; border:1px solid #B00; border-top:none; margin-left:20px; display:none;} #subnav{width:200px;} #subnav .list{ width:200px; height:30px;} #subnav .list h2{ width:160px; height:30px; padding-left:30px; line-height:30px; margin-right:10px;} #subnav .list a:hover, #subnav .active a:hover{ color:#900; font-weight:bold;} #subnav .active{ width:200px; height:30px; border-bottom:1px solid #b00; border-top:1px solid #b00; position:relative;} #subnav .active h2{ width:170px; height:30px; padding-left:30px; line-height:30px; background:#fff; position:absolute; left:1px; top:0; z-index:4;} #subnav .list_nav{ width:500px; overflow:hidden; border:1px solid #b00; position:absolute; left:200px; top:-1px; z-index:3; display:none;} </style> <script type="text/javascript"> window.onload=function() { var oNav=document.getElementById('nav'); var oBox=document.getElementById('box'); var oSubnav=document.getElementById('subnav'); var aLi=oSubnav.getElementsByTagName('li'); var i=0; oNav.onclick=function() { if(oBox.style.display=='block') { oBox.style.display='none'; } else { oBox.style.display='block'; } } for(i=0;i<aLi.length;i++) { if(aLi[i].className=='list') { aLi[i].onmousemove=function() { for(i=0;i<aLi.length;i++) { var aDivList=this.getElementsByTagName('div')[0]; aDivList.style.display='block'; this.className='active'; } } aLi[i].onmouseout=function() { for(i=0;i<aLi.length;i++) { var aDivList=this.getElementsByTagName('div')[0]; aDivList.style.display='none'; this.className='list'; } } } } }; </script> </head> <body> <div id="nav"> <h1>所有商品分类</h1> </div> <div id="box"> <ul id="subnav"> <li> <h2><a href="#">服饰内衣、鞋靴运动</a></h2> <div> <ul> <li>1</li> <li>1</li> <li>1</li> <li>1</li> </ul> </div> </li> <li> <h2><a href="#">电子商品</a></h2> <div> <ul> <li>222</li> <li>2222</li> <li>2222</li> <li>22222</li> </ul> </div> </li> <li> <h2><a href="#">服饰内衣、鞋靴运动</a></h2> <div> <ul> <li>3333</li> <li>3333</li> <li>3333</li> <li>3333</li> </ul> </div> </li> <li> <h2><a href="#">服饰内衣、鞋靴运动</a></h2> <div> <ul> <li>1</li> <li>1</li> <li>1</li> <li>1</li> </ul> </div> </li> </ul> </div> </body> </html>
希望本文所述对大家的javascript程序设计有所帮助。