C# 图片操作 常用方法 总结

    //image to byte[]
       static byte[] Image2Bytes(System.Drawing.Image photo)
       {
            //System.Drawing.Image photo = new System.Drawing.Bitmap(path);
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            photo.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
            byte[] imagedata = ms.GetBuffer();
            return imagedata;
       }

       //byte[] to image
        static System.Drawing.Image Bytes2Image(byte[] imagedata)
        {
            System.IO.MemoryStream ms = new  System.IO.MemoryStream(imagedata);
            System.Drawing.Image b =new  System.Drawing.Bitmap(ms);
            return b;
        }

  //数据库 字段 DbType="Image"  对应类型System.Data.Linq.Binary
       static System.Data.Linq.Binary Image2DBType(System.Drawing.Image image)
       {   

           System.Data.Linq.Binary Barcode=new Binary(Image2Bytes(image));
           return Barcode;
        

       }

   static System.Drawing.Image DBType2Image(System.Data.Linq.Binary  barcode)
       {
           System.Drawing.Image img=Bytes2Image(barcode.ToArray());
           return img;
       }

   // 剪切 并保存
        //在指定原图大小  以及截取的位置和大小 
       public void CutAndSaveImage(System.Drawing.Image originalImage,string dstpath, int cutX, int cutY, int cutWidth, int cutHeight, int drawX, int drawY, int drawWidth, int drawHeight, int PhotoWidth, int PhotoHeight)
        {
            //新建一个bmp图片
            System.Drawing.Image bitmap = new System.Drawing.Bitmap(PhotoWidth, PhotoHeight);

            //新建一个画板
            System.Drawing.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(System.Drawing.Color.White);

            //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 System.Drawing.Rectangle((drawX <= 0 ? 0 : drawX), (drawY <= 0 ? 0 : drawY), drawWidth, drawHeight),
                new System.Drawing.Rectangle((cutX < 0 ? 0 : cutX), (cutY<0 ? 0 : cutY), cutWidth, cutHeight), System.Drawing.GraphicsUnit.Pixel);

            originalImage.Dispose();

            if (File.Exists(dstpath))
                File.Delete(dstpath);

            if (dstpath.EndsWith("jpg"))
                bitmap.Save(dstpath, System.Drawing.Imaging.ImageFormat.Jpeg);
            else if (dstpath.EndsWith("png"))
                bitmap.Save(dstpath, System.Drawing.Imaging.ImageFormat.Png);
            else
                bitmap.Save(dstpath);
         
            bitmap.Dispose();
            g.Dispose();

        }

 originalImage.RotateFlip(RotateFlipType.RotateNoneFlipX);
 originalImage.RotateFlip(RotateFlipType.RotateNoneFlipY);
 originalImage.RotateFlip(RotateFlipType.RotateNoneFlipXY);

 originalImage.RotateFlip(RotateFlipType.Rotate90FlipNone);        originalImage.RotateFlip(RotateFlipType.Rotate270FlipNone);