var $ = function(id){
   itm = null;
   
   if (document.getElementById){
	  itm = document.getElementById(id);
   }
   else if (document.all){
	  itm = document.all[id];
   }
   else if (document.layers){
	  itm = document.layers[id];
   }
   
   return itm;
}

function menu(mid,nid,ncount){
	for(var i=0;i<ncount;i++)
	{		
		if(i == nid){
			$(mid+"_m"+i).className ="select";
			$(mid+i).style.display="block";
		}
		else{
			$(mid+"_m"+i).className ="noselect";
			$(mid+i).style.display="none";
		}
	}
}

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++)
                {
                    if (closeClass!="") _this.$(menus[j]).className = closeClass;
                    _this.$(divs[j]).style.display = "none";
                }
		if (openClass!="") _this.$(menus[this.value]).className = openClass;
		_this.$(menus[this.value]).style.cursor="pointer";
            	_this.$(divs[this.value]).style.display = "block";
		//_this.$(divs[this.value]).style.display = "";
            }
        }
        },
    $ : function(oid){
        if(typeof(oid) == "string")
        return document.getElementById(oid);
        return oid;
    }                
}                
window.onload = function(){                
	var SDmodel = new scrollDoor();              
	//SDmodel.sd(["click_m0","click_m1","click_m2"],["click0","click1","click2"],"select","noselect");
	//SDmodel.sd(["question_m0","question_m1"],["question0","question1"],"select","noselect");
}