本文實(shí)例講述了JS三級(jí)可折疊菜單實(shí)現(xiàn)方法。分享給大家供大家參考，具體如下：
.ASPX代碼：
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="NavigateMenu.aspx.cs" Inherits="NavigateMenu" %>
<!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 runat="server">
<title>無標(biāo)題頁</title>
<script type="text/javascript" src="JScript.js" ></script>
<style type="text/css">
*{
margin: 0px;
padding: 0px;
border:0px;
}
#nav{
width: 600px;
margin: 0px;
padding: 0px;
font-size: 14px;
line-height: 30px;
}
#nav li{
width: 180px;
padding-left: 20px;
padding-bottom: 1px;
list-style-image: none;
list-style-type: none;
background-color: #FFFFFF;
}
#nav a{
padding-left: 20px;
background-color: #BFBFBF;
display: block;
text-decoration: none;
}
#nav a:hover {
background-color: #FF9175;
}
#nav li ul{
padding-top: 1px;
list-style-image: none;
list-style-type: none;
}
#nav li li{
padding-left: 0px;
}
#nav ul a{
background-color: #EBEBEB;
}
.cx {
display:none;
visibility:hidden;
}
.ex {
display:inherit;
visibility:inherit;
}
</style>
<script type="text/javascript" >
window.onload=function(){
statUp();
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div id="Parent">
<ul id="nav">
<li><a href="javascript:void(0);" onclick="doMenu(this,'1')">菜單1</a>
<ul>
<li><a href="javascript:void(0);">菜單1_1</a></li>
<li><a href="javascript:void(0);">菜單1_2</a></li>
</ul>
</li>
<li><a href="javascript:void(0);" onclick="doMenu(this,'1')">菜單2</a>
<ul>
<li><a href="javascript:void(0);" onclick="doMenu(this,'2')" >菜單2_1</a>
<ul>
<li>菜單2_1_1</li>
<li>菜單2_1_2</li>
</ul>
</li>
<li><a href="javascript:void(0);" onclick="doMenu(this,'2')">菜單2_2</a>
<ul>
<li>菜單2_2_1</li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
</form>
</body>
</html>
js文件代碼：
function doMenu(obj,strDeep){
var items=obj.parentNode.getElementsByTagName("ul");
//獲取a 對(duì)象你節(jié)點(diǎn)li 下包含的 所有ul集合
var itmUl;
var deeps=strDeep; //strDeep 為當(dāng)前菜單的級(jí)數(shù)
if(items.length>0){
itmUl=items[0];
alert(itmUl);
}
if(itmUl.className!="ex"){
cxAll();//當(dāng)前節(jié)點(diǎn)為關(guān)閉狀態(tài)時(shí),先執(zhí)行關(guān)閉所有ul子菜單
if(deeps=='2'){ //若要展開三級(jí)菜單當(dāng),還要將其二級(jí)父菜單展開
itmUl.parentNode.parentNode.className="ex";
}
itmUl.className="ex"; //展開下級(jí)菜單
}else{
itmUl.className="cx";
}
}
function statUp(){
cxAll();
var ulDom=document.getElementById("nav");
var items=ulDom.getElementsByTagName("ul");
}
function cxAll(){
var ulDom=document.getElementById("nav");
var items=ulDom.getElementsByTagName("ul");
for (var i=0;i<items.length;i++)
{
items[i].className="cx";
}
}
希望本文所述對(duì)大家JavaScript程序設(shè)計(jì)有所幫助。