C#生成缩略图

print?/// 生成缩略图
    /// </summary>
    /// <param name="originalImagePath">源图路径</param>
    /// <param name="thumbnailPath">缩略图路径</param>
    /// <param name="width">缩略图宽度</param>
    /// <param name="height">缩略图高度</param>
    /// <param name="mode">生成缩略图的方式:HW指定高宽缩放(可能变形);W指定宽，高按比例 H指定高，宽按比例 Cut指定高宽裁减(不变形)</param>　　
    /// <param name="mode">要缩略图保存的格式(gif,jpg,bmp,png) 为空或未知类型都视为jpg</param>　　
    public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode, string imageType)
    {
        Image originalImage = Image.FromFile(originalImagePath);
        int towidth = width;
        int toheight = height;
        int x = 0;
        int y = 0;
        int ow = originalImage.Width;
        int oh = originalImage.Height;
        switch (mode)
        {
            case "HW"://指定高宽缩放（可能变形）　　　　　　　　
                break;
            case "W"://指定宽，高按比例　　　　　　　　　　
                toheight = originalImage.Height * width / originalImage.Width;
                break;
            case "H"://指定高，宽按比例
                towidth = originalImage.Width * height / originalImage.Height;
                break;
            case "Cut"://指定高宽裁减（不变形）　　　　　　　　
                if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
                {
                    oh = originalImage.Height;
                    ow = originalImage.Height * towidth / toheight;
                    y = 0;
                    x = (originalImage.Width - ow) / 2;
                }
                else
                {
                    ow = originalImage.Width;
                    oh = originalImage.Width * height / towidth;
                    x = 0;
                    y = (originalImage.Height - oh) / 2;
                }
                break;
            default:
                break;
        }
        //新建一个bmp图片
        Image bitmap = new System.Drawing.Bitmap(towidth, toheight);
        //新建一个画板
        Graphics g = System.Drawing.Graphics.FromImage(bitmap);
        //设置高质量插值法
        g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
        //设置高质量,低速度呈现平滑程度
        g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
        //清空画布并以透明背景色填充
        g.Clear(Color.Transparent);
        //在指定位置并且按指定大小绘制原图片的指定部分
        g.DrawImage(originalImage, new Rectangle(0, 0, towidth, toheight),
           new Rectangle(x, y, ow, oh),
           GraphicsUnit.Pixel);
        try
        {
            //以jpg格式保存缩略图
            switch (imageType.ToLower())
            {
                case "gif":
                    bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Gif);
                    break;
                case "jpg":
                    bitmap.Save(thumbnailPath, Sy

补充：软件开发 , C# ,