JavaScript控制鼠标滑轮事件

<script language="JavaScript">
<!--
//document.body.onmousewheel = function(){alert('你在滚，哈哈');}

function img_zoom(e, o){ //图片鼠标滚轮缩放
   var zoom = parseInt(o.style.zoom, 10) || 100;
   zoom += event.wheelDelta / 24;
   if (zoom >0) o.style.zoom = zoom + '%';
   return false;
}
//-->
</script>
<img onmousewheel="return img_zoom(event,this)" src="bannner.jpg?http://www.xvna.com" width="500" height="500">