图像形式转换

　　　　 //图形转换  Bitmap=>Image
        private System.Windows.Controls.Image Bitmap2Image(System.Drawing.Bitmap Bi)
        {
            MemoryStream ms = new MemoryStream();
            Bi.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
            BitmapImage bImage = new BitmapImage();
            bImage.BeginInit();
            bImage.StreamSource = new MemoryStream(ms.ToArray());
            bImage.EndInit();
            ms.Dispose();
            Bi.Dispose();
            System.Windows.Controls.Image i = new System.Windows.Controls.Image();
            i.Source = bImage;
            return i;
        }
　　　　 //ImageSource给WPF的Image控件设置图片地址
        private System.Windows.Media.ImageSource ConvertDrawingImage2MediaImageSource(System.Drawing.Image image)
        {
            var ms = new MemoryStream();

            var bitmap = new System.Windows.Media.Imaging.BitmapImage();
            bitmap.BeginInit();

            image.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
            ms.Seek(0, System.IO.SeekOrigin.Begin);
            bitmap.StreamSource = ms;
            bitmap.EndInit();
            return bitmap;
        }
        //将16进制字符串转成Byte[]，这样可以使用MemoryStream来构建图片
        private byte[] strToToHexByte(string hexString)
        {
            hexString = hexString.Replace(" ", "");
            if ((hexString.Length % 2) != 0)
                hexString += " ";
            byte[] returnBytes = new byte[hexString.Length / 2];
            for (int i = 0; i < returnBytes.Length; i++)
                returnBytes[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16);
            return returnBytes;
        }