JS实现网页Div层Clone拖拽效果

本文实例讲述了JS实现网页Div层Clone拖拽效果。分享给大家供大家参考。具体如下：

这是一个层拖动，网页上的拖拽Clone效果实例，两个层可在鼠标的拖动下，任意改变位置，智能判断层级，也就是智能判断自身是否处于最高层，最高处的层是不会被其它层遮挡的。

运行效果截图如下：

在线演示地址如下：

http://demo.jb51.net/js/2015/js-draw-box-clone-style-codes/

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>拖拽--Clone</title>
<style type="text/css">
body,div{margin:0;padding:0;}
body{background:#3e3e3e;}
div{position:absolute;width:100px;height:100px;cursor:move;border:1px solid #888;background:#000;}
#drag1{top:100px;left:100px;}
#drag2{top:100px;left:300px;}
#temp{opacity:0.3;filter:alpha(opacity=30);}
</style>
<script type="text/javascript">
var zIndex = 1;
window.onload = function ()
{
 var oDrag1 = document.getElementById("drag1");
 var oDrag2 = document.getElementById("drag2");
 drag(oDrag1);
 drag(oDrag2);
};
function drag(oDrag)
{
 var disX = dixY = 0;
 oDrag.onmousedown = function (event)
 {
  var event = event || window.event;
  disX = event.clientX - this.offsetLeft;
  disY = event.clientY - this.offsetTop;
  var oTemp = document.createElement("div");
  oTemp["id"] = "temp";
  oTemp.style.left = this.currentStyle ? this.currentStyle["left"] : getComputedStyle(this, null)["left"];
  oTemp.style.top = this.currentStyle ? this.currentStyle["top"] : getComputedStyle(this, null)["top"];
  oTemp.style.zIndex = zIndex++;
  document.body.appendChild(oTemp);
  document.onmousemove = function (event)
  {
   var event = event || window.event;
   var iL = event.clientX - disX;
   var iT = event.clientY - disY;
   var maxL = document.documentElement.clientWidth - oDrag.offsetWidth;
   var maxT = document.documentElement.clientHeight - oDrag.offsetHeight
   iL <= 0 && (iL = 0);
   iT <= 0 && (iT = 0);
   iL >= maxL && (iL = maxL);
   iT >= maxT && (iT = maxT);
   oTemp.style.left = iL + "px";
   oTemp.style.top = iT + "px";
   return false;
  };
  document.onmouseup = function ()
  {
   document.onmousemove = null;
   document.onmouseup = null;
   oDrag.style.left = oTemp.style.left;
   oDrag.style.top = oTemp.style.top;
   oDrag.style.zIndex = oTemp.style.zIndex;
   document.body.removeChild(oTemp);
   oDrag.releaseCapture && oDrag.releaseCapture()
  };
  this.setCapture && this.setCapture();
  return false
 }
}
</script>
</head>
<body>
<div id="drag1"></div>
<div id="drag2"></div>
</body>
</html>

希望本文所述对大家的JavaScript程序设计有所帮助。