03asp.net=======修改图片的显示大小

public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            string filePath = context.Request.MapPath("/ImageUp/aa.jpg");
            ////创一个小的画布，然后让上传的图片画到画布上，最后保存，那么这张图片变小了。
            //using (Bitmap map = new Bitmap(50, 50))
            //{
            //    using (Graphics g = Graphics.FromImage(map))
            //    {
            //        using (Image img = Image.FromFile(filePath))
            //        {
            //            g.DrawImage(img, 0, 0, map.Width, map.Height);
            //            string newfileName = Guid.NewGuid().ToString();
            //            map.Save(context.Request.MapPath("/ImageUp/"+newfileName+".jpg"),System.Drawing.Imaging.ImageFormat.Jpeg);
            //        }
            //    }
            //}
            string thumbfileName="thumb"+Guid.NewGuid().ToString()+".jpg";
            Common.ImageClass.MakeThumbnail(filePath,context.Request.MapPath (thumbfileName), 50, 50, "W");
        }