var strkey=null;
    function $(id){return document.getElementById(id);}
        function ShowMenu(obj)
		{
		    var tag=obj.getElementsByTagName("ol");
		    if(tag.length>0)
		    {
		        var DropListID="ul"+Math.random();
		        tag[0].setAttribute("id",DropListID);
		        tag[0].style.zIndex="999";
		        tag[0].style.display="block";		        
		        setOffsets(obj,DropListID);  
		        obj.style.background="#FFB56A";
		        obj.onmouseout=function()
		        {
		            tag[0].style.zIndex="-999";
		            tag[0].style.display="none";
		        }
		    }
		}
		//计算显示位置
function calculateOffset(field,attr) {
      var offset = 0;
      while(field) {
          offset += field[attr];
          field = field.offsetParent;
      }
      return offset;
}
function setOffsets(obj,id)
{
	  strkey=obj;
	  AddLiOnMouse();//添加鼠标移动上去的效果
      $(id).style.Width =strkey.offsetWidth+"px";
	  $(id).style.Height=strkey.offsetHeight+"px";
      var left = calculateOffset(strkey, "offsetLeft");
      var top = calculateOffset(strkey, "offsetTop")+strkey.offsetHeight;;
      $(id).style.left = left + "px";
      $(id).style.top = top + "px";
}
function AddLiOnMouse()
{
	var li=strkey.getElementsByTagName("li");
	if(li<=0)
	{
	return;
	}
	for(var i=0;i<li.length;i++)
	{
		li[i].onmouseover=function(){this.style.background='#DCF1FA';}
		li[i].onmouseout=function(){this.style.background='#ffffff';}
	}
}