private void Btn_Upload_Click( object sender, System.EventArgs e )
            {
            if( UploadFile.PostedFile.FileName.Trim( )!="" )
            {
            //上传文件
                    string extension = Path.GetExtension( UploadFile.PostedFile.FileName ).ToUpper( );
            string fileName = DateTime.Now.Year.ToString( ) + DateTime.Now.Month.ToString( ) + DateTime.Now.Day.ToString( ) + DateTime.Now.Hour.ToString( ) + DateTime.Now.Minute.ToString( ) + DateTime.Now.Second.ToString( );
            string path = Server.MapPath( "." ) + "/UploadFile/" + fileName + extension;
            UploadFile.PostedFile.SaveAs( path );
            //加文字水?⒁?这里的代码和以下加图片水印的代码不能共存
                    System.Drawing.Image image = System.Drawing.Image.FromFile( path );
            Graphics g = Graphics.FromImage( image );
            g.DrawImage( image, 0, 0, image.Width, image.Height );
            Font f = new Font( "Verdana", 32 );
            Brush b = new SolidBrush( Color.White );
            string addText = AddText.Value.Trim( );
            g.DrawString( addText, f, b, 10, 10 );
            g.Dispose( );
            //加图片水印
                    System.Drawing.Image image = System.Drawing.Image.FromFile( path );
            System.Drawing.Image copyImage = System.Drawing.Image.FromFile(Server.MapPath( "." ) + "/Alex.gif" );
            Graphics g = Graphics.FromImage( image );
            g.DrawImage( copyImage, new Rectangle( image.Width-copyImage.Width, image.Height-copyImage.Height, copyImage.Width, copyImage.Height ), 0, 0, copyImage.Width, copyImage.Height, GraphicsUnit.Pixel );
            g.Dispose( );
            //保存加水印过后的图片,删除原始图片
                    string newPath = Server.MapPath( "." ) + "/UploadFile/" + fileName + "_new" + extension;
            image.Save( newPath );
            image.Dispose( );
            if( File.Exists( path ) )
            {
            File.Delete( path );
            }
            Response.Redirect( newPath );
            }
            }