ASP.NET 2.0,C#----图像特效处理

              try
              {
                  bitmap.Save(Server.MapPath("./_Big.jpg"), System.Drawing.Imaging.ImageFormat.Jpeg);
                  MessageShow("已经生成图片，路径为" + @Server.MapPath("./_Big.jpg").Replace("", ""));

              }
              catch (Exception ex)
              {
                  MessageShow("生成图片错误！" + ex.Message);
                  throw;
              }
              graphics.Dispose();
              bitmap.Dispose();
          }

          //缩小为原始图像的1/(X*X)
          protected void btnSmall_Click(object sender, EventArgs e)
          {
              float i = float.Parse(txtBig.Text.Trim());
              System.Drawing.Image img = System.Drawing.Image.FromFile(path);
              int w = Convert.ToInt32(img.Width / i);
              int h = Convert.ToInt32(img.Height / i);

              // 防止过度变形
              if (w < 1) w = 10;
              if (h < 1) h = 0;
              bitmap = new Bitmap(w, h);
              graphics = Graphics.FromImage(bitmap);
              graphics.DrawImage(img, 0, 0, w, h);
              try
              {