C#生成二维码，把二维码图片放入Excel中

  /// <summary>        /// 把图片保存到excel中        /// </summary>        /// <param name="excelFilePath">目标Excel</param>        /// <param name="imageFilePath">保存的图片</param>        /// <param name="width">保存时图片宽度</param>        /// <param name="height">保存时图片高度</param>        /// <param name="col">Excel第几列开始放</param>        /// <param name="row">Excel第几行开始放</param>        public static void InsertImgToExcel(string excelFilePath, string imageFilePath,int width,int height,int col,int row)        {            try            {                FileStream fs = new FileStream(excelFilePath, FileMode.Open, Fileaccess.ReadWrite);                HSSFWorkbook hssfworkbook = new HSSFWorkbook(fs);                ISheet sheet1 = hssfworkbook.GetSheetAt(0);                //map the path to the img folder                string imagesPath = imageFilePath;                //create an image from the path                System.Drawing.Image image = System.Drawing.Image.FromFile(imagesPath);                MemoryStream ms = new MemoryStream();                //pull the memory stream from the image (I need this for the byte array later)                image.Save(ms, System.Drawing.Imaging.ImageFormat.Png);                //the drawing patriarch will hold the anchor and the master information                IDrawing patriarch = sheet1.CreateDrawingPatriarch();                //store the coordinates of which cell and where in the cell the image goes                HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0, 100, 100, col, row, col+3, row+3);                //types are 0, 2, and 3. 0 resizes within the cell, 2 doesn't                anchor.AnchorType = 2;                //add the byte array and encode it for the excel file                int index = hssfworkbook.AddPicture(ms.ToArray(), PictureType.JPEG);                ipicture pict = patriarch.CreatePicture(anchor, LoadImage(imagesPath, hssfworkbook));                pict.Resize();//原图大小                FileStream fs3 = new FileStream(excelFilePath, FileMode.OpenOrCreate);                hssfworkbook.Write(fs3);                fs3.Close();                fs.Close();}

　　生成二维码

 /// <summary>        /// 生成二维码图片        /// </summary>        /// <param name="codeNumber">要生成二维码的字符串</param>             /// <param name="size">大小尺寸</param>        /// <returns>二维码图片</returns>        public Bitmap Create_ImgCode(string codeNumber, int size)        {            //创建二维码生成类            QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();            //设置编码模式            qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;            //设置编码测量度            qrCodeEncoder.QRCodeScale = size;            //设置编码版本            qrCodeEncoder.QRCodeVersion = 0;            //设置编码错误纠正            qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;            //生成二维码图片            System.Drawing.Bitmap image = qrCodeEncoder.Encode(codeNumber);            return image;        }

　　用上面方法生成二维码有个问题，当数据量特别大的时候就生成不了。后面换了zxing来生成二维码，生成的数据多一点

 1 public static Bitmap Create(string str) 2         { 3             EncodingOptions options = null; 4             BarcodeWriter writer = null; 5  6             options = new QrCodeEncodingOptions 7             { 8                 DisableECI = true, 9                 CharacterSet = "UTF-8",10                 Margin = 0,11                 Width = 125,12                 Height = 12513             };14             writer = new BarcodeWriter();15             writer.Format = BarcodeFormat.QR_CODE;16             writer.Options = options;17             return writer.Write(str);18         }

生成出来的二维码有可能周围的空白处有点多，初步测试可能是由于信息量过大，二维码如果按照原始块间距生成的话会导致超过固定的大小，因此自动减小块间距导致生成的没有固定大小大，留有空白

利用仪器扫描一张图片中某个部分含有二维码，如果图片过大，我遇到过3000*2400左右大小的，用二维码解析根本解析不出来，只有按照二维码的位置进行剪切裁剪后再解析二维码，能实现

  /// <summary>        /// 剪裁 -- 用GDI+         /// </summary>        /// <param name="b">原始Bitmap</param>        /// <returns>剪裁后的Bitmap</returns>        public static Bitmap Cut(Bitmap b)        {            if (b == null)            {                return null;            }            int startX = b.Width * 3 / 4;            int startY = 0;            int width = b.Width / 4;            int height = b.Height / 4;            try            {                Bitmap bmpOut = new Bitmap(width, height, PixelFormat.Format24bpPRgb);                Graphics g = Graphics.FromImage(bmpOut);                g.DrawImage(b, new Rectangle(0, 0, width, height), new Rectangle(startX, startY, width, height), GraphicsUnit.Pixel);                g.Dispose();                return bmpOut;            }            catch            {                return null;            }        }        /// <summary>        /// 剪裁 -- 用GDI+         /// </summary>        /// <param name="b">原始Bitmap</param>        /// <param name="StartX">开始坐标X</param>        /// <param name="StartY">开始坐标Y</param>        /// <param name="iWidth">宽度</param>        /// <param name="iHeight">高度</param>        /// <returns>剪裁后的Bitmap</returns>        public static Bitmap Cut(Bitmap b, int StartX, int StartY, int iWidth, int iHeight)        {            if (b == null)            {                return null;            }            int w = b.Width;            int h = b.Height;            if (StartX >= w || StartY >= h)            {                return null;            }            if (StartX + iWidth > w)            {                iWidth = w - StartX;            }            if (StartY + iHeight > h)            {                iHeight = h - StartY;            }            try            {                Bitmap bmpOut = new Bitmap(iWidth, iHeight, PixelFormat.Format24bppRgb);                Graphics g = Graphics.FromImage(bmpOut);                g.DrawImage(b, new Rectangle(0, 0, iWidth, iHeight), new Rectangle(StartX, StartY, iWidth, iHeight), GraphicsUnit.Pixel);                g.Dispose();                return bmpOut;            }            catch            {                return null;            }        }