分别用两个函数实现的菜单_javascript技巧

css+div做的菜单：一个主显示层，别的列表都隐藏着，用js函数设置列表的显示和隐藏。分别用到了两个函数，函数实现的效果是一样的，一个是参考的《css+Dhtml精髓》书上的事例，一个是找的函数。
大家帮我看看那个函数好用！还有大家还有别的更好的方法实现这个效果吗？谢谢！！

<font color=red><!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=gb2312" /> <title>菜单</title>  <style type="text/css">    </style>    <script language="javascript">//判断浏览器         browser = navigator.appName;         browserNum = parseInt(navigator.appVersion);                  if ((browser == "Netscape") && (browserNum < 5))         {             // Netscape 4.x             layerRef = "document.layers['";             endLayerRef = "']";             styleRef = "";         }         else if ((browser == "Netscape") && (browserNum >= 5))         {             // Netscape 6             layerRef = "document.getElementById('";             styleRef = ".style";             endLayerRef = "')";         }         else         {             // Internet Explorer             layerRef = "document.all['";             endLayerRef = "']";             styleRef = ".style";         }     //第一个函数         function showMenu(layerName)         {             // show the layer the user wants to see             eval(layerRef + layerName + endLayerRef + styleRef + ".visibility = 'visible'");             }          function hiddenMenu(layerName)         {             // hidden the layer               eval(layerRef + layerName + endLayerRef + styleRef + ".visibility = 'hidden'");             }                           //第一个函数                          //第二个函数                 function MM_showHideLayers()      {          var i,p,v,obj,args=MM_showHideLayers.arguments;         for (i=0; i<(args.length-2); i+=3)              if ((obj=MM_findObj(args[i]))!=null)              {                  v=args[i+2];                 if (obj.style)                  {                      obj=obj.style;                      v=(v=='show')?'visible':(v='hide')?'hidden':v;                  }                 obj.visibility=v;              }     }       function MM_findObj(n, d)     {         var p,i,x;         if(!d)             d=document;         if((p=n.indexOf("?"))>0&&parent.frames.length)         {             d=parent.frames[n.substring(p+1)].document;             n=n.substring(0,p);         }         if(!(x=d[n])&&d.all)             x=d.all[n];          for (i=0;!x&&i<d.forms.length;i++)             x=d.forms[i][n];         for(i=0;!x&&d.layers&&i<d.layers.length;i++)             x=MM_findObj(n,d.layers[i].document);         if(!x && document.getElementById)             x=document.getElementById(n);         return x;     }     //第二个函数             </script>                           </head> <body>  <div id="nav">  <ul id="ul">      <li><a href="#" onMouseOver="javascript:showMenu('shui')";         onMouseOut="javascript:hiddenMenu('shui')"  >水果/水果</a> </li>          <li><a href="#"   onmouseover="javascript:MM_showHideLayers('hua','','show')";                  onmouseout="javascript:MM_showHideLayers('hua','','hide')">花卉/花卉/花卉</a></li>                                           <li><a href="#"  onmouseover="javascript:MM_showHideLayers('che','','show')";                  onmouseout="javascript:MM_showHideLayers('che','','hide')">汽车/汽车</a></li> <li><a href="#" onmouseover="javascript:MM_showHideLayers('shui','','show')";                  onmouseout="javascript:MM_showHideLayers('shui','','hide')">水果2</a></li> <li><a href="#" onmouseover="javascript:MM_showHideLayers('hua','','show')";                  onmouseout="javascript:MM_showHideLayers('hua','','hide')" >花卉/花卉/花卉2</a></li> <li><a href="#" onmouseover="javascript:MM_showHideLayers('che','','show')";                  onmouseout="javascript:MM_showHideLayers('che','','hide')">汽车/汽车2</a></li> <li><a href="#" onmouseover="javascript:MM_showHideLayers('shui','','show')";                  onmouseout="javascript:MM_showHideLayers('shui','','hide')">水果3</a></li> <li><a href="#" onmouseover="javascript:MM_showHideLayers('hua','','show')";                  onmouseout="javascript:MM_showHideLayers('hua','','hide')">花卉/花卉3</a></li> <li><a href="#" onmouseover="javascript:MM_showHideLayers('che','','show')";                  onmouseout="javascript:MM_showHideLayers('che','','hide')">汽车/汽车/汽车3</a></li> </ul>   </div>     <ul  id="shui"  onMouseOver="javascript:showMenu('shui')";         onMouseOut="javascript:hiddenMenu('shui')" > <li><a href="#" >苹果</a></li> <li><a href="#" >香蕉</a></li> <li><a href="#" >猕猴桃</a></li> <li><a href="#" >火龙果</a></li> <li><a href="#" >苹果2</a></li> <li><a href="#" >香蕉2</a></li> <li><a href="#" >猕猴桃2</a></li> <li><a href="#" >火龙果2</a></li> <li><a href="#" >猕猴桃3</a></li> <li><a href="#" >火龙果3</a></li> </ul> <ul  id="hua"   onmouseover="javascript:MM_showHideLayers('hua','','show')";                  onmouseout="javascript:MM_showHideLayers('hua','','hide')"> <li><a href="#" >菊花</a></li> <li><a href="#" >玫瑰</a></li> <li><a href="#" >牡丹</a></li> <li><a href="#" >茉莉</a></li> <li><a href="#" >君子兰</a></li> <li><a href="#" >虞美人</a></li> <li><a href="#" >喇叭花2</a></li> <li><a href="#" >桂花2</a></li> </ul> <ul  id="che"  onmouseover="javascript:MM_showHideLayers('che','','show')";                  onmouseout="javascript:MM_showHideLayers('che','','hide')"> <li><a href="#" >大众</a></li> <li><a href="#" >奥迪</a></li> <li><a href="#" >宝马</a></li> <li><a href="#" >奔驰</a></li> <li><a href="#" >保时捷</a></li> <li><a href="#" >福特</a></li> <li><a href="#" >克莱斯勒</a></li> <li><a href="#" >法拉利</a></li> <li><a href="#" >克莱斯勒2</a></li> <li><a href="#" >法拉利2</a></li> </ul>     </body> </html> </font>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]

分别用两个函数实现的菜单_javascript技巧_