鼠标滚轮 放大缩小图片

js实现鼠标滚轮放大缩小图片
<script>
//放大缩小图片
function sdZoom(o)
{
var zoom=parseInt(o.style.zoom,10)||100;
zoom+=event.wheelDelta/12;
if(zoom>0)o.style.zoom=zoom+'%';
return false;
}
</script>
<!--嵌入js代码-->
<img src="/images/home.jpg" width="600" onmousewheel="return sdZoom(this)" onload="javascript:if(this.width>screen.width-0)this.style.width=screen.width-0;">
<!--图片调用代码-->