function scrollDoor(){
}
scrollDoor.prototype = {
sd : function(menus,divs,openClass,closeClass){
   var _this = this;
   if(menus.length != divs.length)
   {
    alert("菜单层数量和内容层数量不一样!");
    return false;
   }    
   for(var i = 0 ; i < menus.length ; i++)
   { 
    _this.$(menus[i]).value = i;    
    _this.$(menus[i]).onmouseover = function(){
     
     for(var j = 0 ; j < menus.length ; j++)
     {      
      _this.$(menus[j]).className = closeClass;
      _this.$(divs[j]).style.display = "none";
     }
     _this.$(menus[this.value]).className = openClass; 
     _this.$(divs[this.value]).style.display = "block";  

  
    }
   }
   },
$ : function(oid){
   if(typeof(oid) == "string")
   return document.getElementById(oid);
   return oid;
}
}