图片适应屏幕并鼠标滚动缩放的代码

<script language="javascript">
function bbimg(o){
var zoom=parseInt(o.style.zoom, 10)||100;zoom+=event.wheelDelta/12;if (zoom>0) o.style.zoom=zoom+"%";
return false;
}
</script>

<img SRC="pic/124.jpg" border=0 onmousewheel="return bbimg(this)" onload="javascript:if(this.width>screen.width-100)this.style.width=screen.width-100;">