C# 剪裁圖片並保存

最近需要將一張圖片上傳並按指定位置剪裁，後來在網上找了一個剪裁圖片的插件，但是只有前臺沒有後端，然後我各種百度，並最終完成，特此寫一篇博客略表紀念。

前臺我就不說了，用的cropper插件，有興趣的自己去百度找找吧。jQuery之家 有這個插件。

下麵是代碼：

        HttpPostedFile file = context.Request.Files["avatar_file"];
        string datasize = context.Request.Params["avatar_data"];
        //{"x":30.003846153846148,"y":16.715384615384625,"height":300.8,"width":300.8,"rotate":0}     剪裁之後參數
        JavaScriptSerializer jss = new JavaScriptSerializer();
        ImgSize imagesize = jss.Deserialize<ImgSize>(datasize);

        byte[] FileByte = SetFileToByteArray(file);//圖片數組
        string strtExtension = System.IO.Path.GetExtension(file.FileName);//圖片格式

        MemoryStream ms1 = new MemoryStream(FileByte);
        Bitmap sBitmap = (Bitmap)Image.FromStream(ms1);
        Rectangle section = new Rectangle(new Point(imagesize.ToInt(imagesize.x), imagesize.ToInt(imagesize.y)), new Size(imagesize.ToInt(imagesize.width), imagesize.ToInt(imagesize.height)));
        Bitmap CroppedImage = MakeThumbnailImage(sBitmap, section.Width, section.Height, section.Width, section.Height, section.X, section.Y);

上面代碼中用到我自己創建了一個ImgSize類，代碼如下：

    class ImgSize
    {
        //{"x":30.003846153846148,"y":16.715384615384625,"height":300.8,"width":300.8,"rotate":0}
        public double x { get; set; }
        public double y { get; set; }
        public double width { get; set; }
        public double height { get; set; }
        public int rotate { get; set; }

        public int ToInt(double doubleValue)
        {
            return Convert.ToInt32(doubleValue);
        }
    }

上面代碼中使用到的幾個方法：

文件轉化：

    /// <summary>
    /// 將From表單file文件轉化為byte數組
    /// </summary>
    /// <param name="File">from提交文件流</param>
    /// <returns></returns>
    private byte[] SetFileToByteArray(HttpPostedFile File)
    {
        Stream stream = File.InputStream;
        byte[] AyyayByte = new byte[File.ContentLength];
        stream.Read(AyyayByte, 0, File.ContentLength);
        stream.Close();
        return AyyayByte;
    }

核心剪裁方法：

    /// <summary>
    /// 裁剪圖片並保存
    /// </summary>
    /// <param name="Image">圖片信息</param>
    /// <param name="maxWidth">縮略圖寬度</param>
    /// <param name="maxHeight">縮略圖高度</param>
    /// <param name="cropWidth">裁剪寬度</param>
    /// <param name="cropHeight">裁剪高度</param>
    /// <param name="X">X軸</param>
    /// <param name="Y">Y軸</param>
    public static Bitmap MakeThumbnailImage(Image originalImage, int maxWidth, int maxHeight, int cropWidth, int cropHeight, int X, int Y)
    {
        Bitmap b = new Bitmap(cropWidth, cropHeight);
        try
        {
            using (Graphics g = Graphics.FromImage(b))
            {
                //清空畫布並以透明背景色填充
                g.Clear(Color.Transparent);
                //在指定位置並且按指定大小繪製原圖片的指定部分
                g.DrawImage(originalImage, new Rectangle(0, 0, cropWidth, cropHeight), X, Y, cropWidth, cropHeight, GraphicsUnit.Pixel);
                Image displayImage = new Bitmap(b, maxWidth, maxHeight);
                displayImage.Save("E:\\cutimg.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
                Bitmap bit = new Bitmap(b, maxWidth, maxHeight);
                return bit;
            }
        }
        catch (System.Exception e)
        {
            throw e;
        }
        finally
        {
            originalImage.Dispose();
            b.Dispose();
        }
    }

最後的結果是把存到了E盤根目錄下麵