简单实用特效代码，打开一个层后可以拖动

<style type="text/css"> body { margin: 0px; } #div1 { display: none; position: absolute; z-index: 1000; height: 100%; width: 100%; background: #000000; filter:Alpha(opacity=30); } #div2 { display: none; position: absolute; height: 100%; width: 100%; padding-top: 10%; z-index: 1001; } #div3 { display: block; position: absolute; z-index: 999; } </style> <script type="text/javascript"> //定义移动对象和移动坐标 var Mouse_Obj="none",_x,_y; //拖动对象函数(自动) document.onmousemove=function() { if(Mouse_Obj!=="none") { document.getElementById(Mouse_Obj).style.left=_x+event.x; document.getElementById(Mouse_Obj).style.top=_y+event.y; event.returnValue=false; } } //停止拖动函数(自动) document.onmouseup=function() { Mouse_Obj="none"; } //确定被拖动对象函数 o为被拖动对象 function m(o) { Mouse_Obj=o; _x=parseInt(document.getElementById(Mouse_Obj).style.left)-event.x; _y=parseInt(document.getElementById(Mouse_Obj).style.top)-event.y; } </script> <div id="div1"></div> <div id="div2" onmousedown="m(this.id)" style="left: 0px;top: 0px;"> <table width="50%" border="0" cellpadding="3" cellspacing="1" style="background: #ff7300; position:static;filter:progid:DXImageTransform.Microsoft.DropShadow (color=#666666,offX=4,offY=4,positives=true)" align="center"> <tr style="cursor: move;"> <td><font color="#FFFFFF">温馨提示：</font></td> <td align="right"><input type="button" value="ｘ" onClick="document.getElementById ('div1').style.display='none';document.getElementById ('div2').style.display='none';" style="cursor: hand;"></td> </tr> <tr> <td colspan="2" width="100%" bgcolor="#FFFFFF" height="150" align="middle">欢迎访问　<a href="http://www.knowsky.com">http://www.knowsky.com</a></td> </tr> </table> </div> <div id="div3"><input type="button" value="打开层" onClick="document.getElementById ('div1').style.display='block';document.getElementById ('div2').style.display='block';"></div>