获取对象的坐标

function  getPosition(Obj)
{
     var  sumTop = 0 ;
     var  sumLeft = 0 ;    
     while (Obj != window.document.body) {
      sumTop += Obj.offsetTop;
       if (Obj.tagName.toLowerCase() == ' div ' ) {
        sumTop -= Obj.scrollTop;
      }
      sumLeft += Obj.offsetLeft;
      Obj = Obj.offsetParent;
    }
  return  {left:sumLeft,top:sumTop}
}

  var  pos  =  getPosition(handle);
  var  t  =  pos.top;
  var  l = pos.left;