js折叠导航代码

<style type="text/css">
#nav ul.collapsed {
 display: none;
}
</style>
<div style="width:300px">
<ul id="nav">

<li><a href="#Menu=ChildMenu1"  onclick="DoMenu('ChildMenu1')">热淘网</a>
 <ul id="ChildMenu1" class="collapsed">
 <li><a href="http://www.51xuediannao.com">热淘网</a></li>
 <li><a href="http://www.51xuediannao.com/js">js代码</a></li>
 <li><a href="http://www.51xuediannao.com">热淘网</a></li>
 <li><a href="http://www.51xuediannao.com/js">js代码</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 </ul>
</li>

<li><a href="#Menu=ChildMenu2" onclick="DoMenu('ChildMenu2')">热淘网</a>
 <ul id="ChildMenu2" class="collapsed">
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 </ul>
</li>
<li><a href="#Menu=ChildMenu3" onclick="DoMenu('ChildMenu3')">热淘网</a>
 <ul id="ChildMenu3" class="collapsed">
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 <li><a href="#">热淘网</a></li>
 </ul>
</li>

</ul>
</div>
<script type=text/javascript><!--
var LastLeftID = "";
function menuFix() {
 var obj = document.getElementById("nav").getElementsByTagName("li");
 
 for (var i=0; i<obj.length; i++) {
  obj[i].onmouseover=function() {
   this.className+=(this.className.length>0? " ": "") + "sfhover";
  }
  obj[i].onMouseDown=function() {
   this.className+=(this.className.length>0? " ": "") + "sfhover";
  }
  obj[i].onMouseUp=function() {
   this.className+=(this.className.length>0? " ": "") + "sfhover";
  }
  obj[i].onmouseout=function() {
   this.className=this.className.replace(new RegExp("( ?|^)sfhover\\b"), "");
  }
 }
}
function DoMenu(emid)
{
 var obj = document.getElementById(emid);
 obj.className = (obj.className.toLowerCase() == "expanded"?"collapsed":"expanded");
 if((LastLeftID!="")&&(emid!=LastLeftID)) //关闭上一个Menu
 {
  document.getElementById(LastLeftID).className = "collapsed";
 }
 LastLeftID = emid;
}
function GetMenuID()
{
 var MenuID="";
 var _paramStr = new String(window.location.href);
 var _sharpPos = _paramStr.indexOf("#");
 
 if (_sharpPos >= 0 && _sharpPos < _paramStr.length - 1)
 {
  _paramStr = _paramStr.substring(_sharpPos + 1, _paramStr.length);
 }
 else
 {
  _paramStr = "";
 }
 
 if (_paramStr.length > 0)
 {
  var _paramArr = _paramStr.split("&");
  if (_paramArr.length>0)
  {
   var _paramKeyVal = _paramArr[0].split("=");
   if (_paramKeyVal.length>0)
   {
    MenuID = _paramKeyVal[1];
   }
  }
  /*
  if (_paramArr.length>0)
  {
   var _arr = new Array(_paramArr.length);
  }
 
  //取所有#后面的，菜单只需用到Menu
  //for (var i = 0; i < _paramArr.length; i++)
  {
   var _paramKeyVal = _paramArr[i].split('=');
   
   if (_paramKeyVal.length>0)
   {
    _arr[_paramKeyVal[0]] = _paramKeyVal[1];
   }  
  }
  */
 }
 
 if(MenuID!="")
 {
  DoMenu(MenuID)
 }
}
GetMenuID(); //*这两个function的顺序要注意一下，不然在Firefox里GetMenuID()不起效果
menuFix();
--></script>