/**    
功能:拖动对象,并置当前对象为最高层    
作者:feifengxlq《许立强》feifengxlq@hotmail.com    
时间: 2006-10-24    
演示:    
*/     
var move_obj_x0=0,move_obj_y0=0,move_obj_x1=0,move_obj_y1=0;//(x0,y0)为开始拖动时鼠标的位置(x1,y1)为开始拖动时对象的位置     
var obj_moveable=false;      
//开始拖动;     
function startDrag(obj,id)     
{     
 if(event.button==1)     
 {     
 obj.setCapture();     
 win=document.getElementById(id)     
 move_obj_x0 = event.clientX;     
 move_obj_y0 = event.clientY;     
 move_obj_x1 = parseInt(win.style.left);     
 move_obj_y1 = parseInt(win.style.top);     
 obj_moveable = true;     
 }     
}     
//拖动;     
function drag(id)     
{     
 if(obj_moveable)     
 {     
 win=document.getElementById(id)      
php程序员之家
  win.style.left = (move_obj_x1 + event.clientX - move_obj_x0>0)?move_obj_x1 + event.clientX - move_obj_x0:0;     
 win.style.top = (move_obj_y1 + event.clientY - move_obj_y0>0)?move_obj_y1 + event.clientY - move_obj_y0:0;     
 }     
}     
//停止拖动;     
function stopDrag(obj,id)     
{     
 if(obj_moveable)     
 {     
 obj.releaseCapture();     
 obj_moveable = false;     
 }     
}
<!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=gb2312" />     
<title>Untitled Document</title>     
<script language="javascript" src="../src/js/move.js"></script>      
www~phperz~com </head>      
<body>     
<div id="move_test" style="position:absolute">     
<table width="300" border="1" cellspacing="0" cellpadding="0" onmousedown="startDrag(this,'move_test')" onmouseup="stopDrag(this,'move_test')" onmousemove="drag('move_test')">     
 <tr>     
 <td height="30"><div align="center">标题</div></td>     
 </tr>     
</table>     
<table width="300" border="1" cellspacing="0" cellpadding="0">     
 <tr>     
 <td height="100"><div align="center"><a href="http://www.phpobject.net">http://www.phpobject.net</a></div></td>     
 </tr>     
</table>     
</div>      
www.phperz.com
 </body>     
</html>