自定义网页图片的大小

用户上传的图片可能过大，可以用此限定。
Html：

<div style="width:100px;height:100px;border:1px solid #F1F1EA;text-align:center;vertical-align:middle;">
<a href="<%=rdetail_url%>"><IMG SRC="<%=rmag_url %>"  onload="autoImageSize(this,100,100)" border="0"></a>
</div>

Js:

function autoImageSize(imgObj,setWidth,setHeight){
		var imgWidth = imgObj.width;
		var imgHeight = imgObj.height;
		
		//alert(imgWidth + '===' + imgHeight);
		
		if(imgWidth >= setWidth && imgHeight >= setHeight){
			if(imgWidth > imgHeight){
				imgObj.width = setWidth;
			}else{
				imgObj.height = setHeight;
			}
		}
		
		if(imgWidth <= setWidth && imgHeight <= setHeight){
				imgObj.width = imgWidth;
				imgObj.height = imgHeight;
		}
		
		if(imgWidth >= setWidth && imgHeight <= setHeight){
				imgObj.width = setWidth;
		}
		
		if(imgWidth <= setWidth && imgHeight >= setHeight){
				imgObj.height = setHeight;
		}

	}