(转)按比例缩放图片

看到海东兄的按比例缩放图片 ，我就把我写的js版本的也拿出来show一下，哈哈！
js版本：

function resizeImage(obj, MaxW, MaxH)
{
var imageObject = obj;
var state = imageObject.readyState;
if(state!='complete')
{
setTimeout("resizeImage("+imageObject+","+MaxW+","+MaxH+")",50);
return;
}
var oldImage = new Image();
oldImage.src = imageObject.src;
var dW = oldImage.width;
var dH = oldImage.height;
if(dW>MaxW || dH>MaxH)
{
a = dW/MaxW; b = dH/MaxH;
if( b>a ) a = b;
dW = dW/a; dH = dH/a;
}
if(dW > 0 && dH > 0)
{
imageObject.width = dW;
imageObject.height = dH;
}
}

使用很简单：<img src="../pic.jpg" onload='resizeImage(this,60,90)> 就OK了；同时也附上C#版本的

C#版本---海东兄 /article/4696596.html

1 public static string GetImageSize(string imgUrl,int imgHeight,int imgWidth)
9 {
10 string fileName = System.Web.HttpContext.Current.Server.MapPath(imgUrl);
11 string strResult = string.Empty;
12 if(System.IO.File.Exists(fileName) && imgHeight != 0 && imgWidth != 0)
13 {
14 decimal desWidth;decimal desHeight; //目标宽高
15 System.Drawing.Image objImage = System.Drawing.Image.FromFile(fileName);
16 decimal radioAct = (decimal)objImage.Width/(decimal)objImage.Height; //原始图片的宽高比
17 decimal radioLoc = (decimal)imgWidth/(decimal)imgHeight; //图片位的宽高比
18 if(radioAct > radioLoc) //原始图片比图片位宽
19 {
20 decimal dcmZoom = (decimal)imgWidth/(decimal)objImage.Width;
21 desHeight = objImage.Height*dcmZoom;
22 desWidth = imgWidth;
23 }
24 else
25 {
26 decimal dcmZoom = (decimal)imgHeight/(decimal)objImage.Height;
27 desWidth = objImage.Width*dcmZoom;
28 desHeight = imgHeight;
29 }
30 objImage.Dispose(); //释放资源
31 strResult = "width=\"" + Convert.ToString((int)desWidth) + "\" height=\""
32 + Convert.ToString((int)desHeight) + "\" ";
33 }
34 return strResult;
35 }

<script language="javascript">
function changeImg(mypic){
var xw=160;
var xl=180;

var width = mypic.width;
var height = mypic.height;
var bili = width/height;

var A=xw/width;
var B=xl/height;

if(!(A>1&&B>1))
{
if(A<B)
{
mypic.width=xw;
mypic.height=xw/bili;
}
if(A>B)
{
mypic.width=xl*bili;
mypic.height=xl;
}
}
}
</script>
<img src="sh180.jpg" onload="changeImg(this)">