winfrom 保存图片

 private void btnSave_Click(object sender, EventArgs e)
        {
            SaveFileDialog sfd = new SaveFileDialog();
            sfd.Filter = "BMP (*.bmp)|*.bmp|GIF (*.gif)|*.gif|JPG (*.jpg)|*.jpg|PNG (*.png)|*.png|TIFF (*.tif)|*.tif";
            sfd.AddExtension = true;
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                SaveTypes savetype = SaveTypes.UNSPECIFIED;
                switch (sfd.FilterIndex)
                {
                            //图片格式
                    case 1:  savetype = SaveTypes.BMP; break;
                    case 2:  savetype = SaveTypes.GIF; break;
                    case 3:  savetype = SaveTypes.JPG; break;
                    case 4:  savetype = SaveTypes.PNG; break;
                    case 5:  savetype = SaveTypes.TIFF; break;
                    default: break;
                }
                SaveImage(sfd.FileName, savetype, barcode.Image);
            }
        }

     public enum SaveTypes : int { JPG, BMP, PNG, GIF, TIFF, UNSPECIFIED }

 public void SaveImage(string Filename, SaveTypes FileType, Image image)
        {
            try
            {
                if (image != null)
                {
                    ImageFormat imageformat;
                    switch (FileType)
                    {
                        case SaveTypes.BMP: imageformat = ImageFormat.Bmp; break;
                        case SaveTypes.GIF: imageformat = ImageFormat.Gif; break;
                        case SaveTypes.JPG: imageformat = ImageFormat.Jpeg; break;
                        case SaveTypes.PNG: imageformat = ImageFormat.Png; break;
                        case SaveTypes.TIFF: imageformat = ImageFormat.Tiff; break;
                        default: imageformat = ImageFormat.Bmp; break;
                    }
                    ((Bitmap)image).Save(Filename, imageformat);
                }
            }
            catch (Exception ex)
            {
                throw new Exception(" 无法保存图像。" + ex.Message);
            }
        }