js网格图片拖拽位置和大小变换效果

window.onload = function() {
		var oUl= document.getElementById("drag_div");
		var aLi = oUl.getElementsByTagName('div');
		var disX = 0;
		var disY = 0;
		var minZindex = 1;
		var aPos =[];
		for(var i=0;i<aLi.length;i++){
			var t = aLi[i].offsetTop;
			var l = aLi[i].offsetLeft;
			aLi[i].style.top = t+"px";
			aLi[i].style.left = l+"px";
			aPos[i] = {left:l,top:t};
			aLi[i].index = i;
		}