图片上传并盖水印

图片上传并盖水印
private void UploadImg()
{
int fileCount = Request.Files.Count;
   string UploadFilename;
   string[] AFilename;
   char de ='\\';
   for (int i = 0; i < fileCount; i++)
   {
    HttpPostedFile hpf= Request.Files[i];
    if(hpf.ContentType.ToLower() != "image/gif")
     continue;
    AFilename = hpf.FileName.Split(de);
    
    UploadFilename = AFilename[AFilename.Length - 1];    //得到文件名

    

    if(UploadFilename!="")
    {
     hpf.SaveAs(Server.MapPath(".") + "\\" + UploadFilename);        //保存文件路径
     this.ShowPannel(Server.MapPath(".") + "\\" + UploadFilename);   //在pannel里面显示
    }

    AddTextToImg(UploadFilename,"印章");
          
   }
}

/// <summary>
  /// 给图片盖印
  /// </summary>
  /// <param name="fileName">图片名称</param>
  /// <param name="text">印字符</param>
  private void AddTextToImg(string fileName,string text)
  {
　   if(!File.Exists(MapPath(fileName)))
　   {
　　   throw new FileNotFoundException("The file don't exist!");
　   }

　   if( text == string.Empty )
　   {
　　   return;
　   }
　   //还需要判断文件类型是否为图像类型，这里就不赘述了

　   System.Drawing.Image image = System.Drawing.Image.FromFile(MapPath(fileName));
　   Bitmap bitmap = new Bitmap(image,image.Width,image.Height);
　   Graphics g = Graphics.FromImage(bitmap);

　   float fontSize = 10.0f; //字体大小
　   float textWidth = text.Length*fontSize; //文本的长度
　   //下面定义一个矩形区域，以后在这个矩形里画上白底黑字
　   float rectX = 0;
　   float rectY = 0;
　   float rectWidth = text.Length*(fontSize+8);
　   float rectHeight = fontSize+8;
　   //声明矩形域
　   RectangleF textArea = new RectangleF(rectX,rectY,rectWidth,rectHeight);

　   Font font = new Font("宋体",fontSize); //定义字体
　   Brush whiteBrush = new SolidBrush(Color.White); //白笔刷，画文字用
　   Brush blackBrush = new SolidBrush(Color.Transparent); //透明刷，画背景用

　   g.FillRectangle(blackBrush,rectX,rectY,rectWidth,rectHeight);

　   g.DrawString(text,font,whiteBrush,textArea);
　   MemoryStream ms = new MemoryStream( );
　   //保存为Jpg类型
　   bitmap.Save(ms,ImageFormat.Jpeg);

　   //输出处理后的图像，这里为了演示方便，我将图片显示在页面中了
　   Response.Clear();
　   Response.ContentType = "image/jpeg";
　   Response.BinaryWrite( ms.ToArray() );

　   g.Dispose();　
　   bitmap.Dispose();
　   image.Dispose();
  }