可以拖动的div

function beginDrag(elementToDrag,event) 
{ 
var deltaX=event.clientX-parseInt(elementToDrag.style.left); 
var deltaY=event.clientY-parseInt(elementToDrag.style.top); 
if(document.addEventListener) 
{ 
document.addEventListener(”mousemove”,moveHandler,true); 
document.addEventListener(”mouseup”,upHandler,true); 
//document.addEventListener(”mouseout”,upHandler,true); 
} 
else if(document.attachEvent) 
{ 
document.attachEvent(”onmousemove”,moveHandler); 
document.attachEvent(”onmouseup”,upHandler); 
//document.attachEvent(”onmouseout”,upHandler); 
} 
if(event.stopPropagation) event.stopPropagation(); 
else event.cancelBubble=true; 
if(event.preventDefault) event.preventDefault(); 
else event.returnValue=false; 
function moveHandler(e) 
{ 
　　if (!e) e=window.event; //如果是IE的事件对象，那么就用window.event 
　　//全局属性，否则就用DOM二级标准的Event对象。 
elementToDrag.style.left=(e.clientX-deltaX)+”px”; 
elementToDrag.style.top=(e.clientY-deltaY)+”px”; 
if(e.stopPropagation) e.stopPropagation(); 
else e.cancelBubble=true; 
} 
function upHandler(e) 
{ 
if(document.removeEventListener) 
{ 
document.removeEventListener(”mouseup”,upHandler,true); 
document.removeEventListener(”mousemove”,moveHandler,true);} 
else 
{ 
document.detachEvent(”onmouseup”,upHandler); 
document.detachEvent(”onmousemove”,moveHandler);} 
} 
if (!e) e=window.event; 
if(e.stopPropagation) e.stopPropagation(); 
else e.cancelBubble=true; 
}