使用c#读取/解析二维码

使用zxing.net组件，读取BitmapSource中的二维码。简单使用方法如下：

        private void DecodeQrCode()
        {
            if (QrCodeSource.CanFreeze)
            {
                QrCodeSource.Freeze();
            }
            using (var bitmap = BitmapSourceToBitmap(QrCodeSource))
            {
                var source = new BitmapLuminanceSource(bitmap);
                var bBitmap = new BinaryBitmap(new HybridBinarizer(source));
                var result = new MultiFormatReader().decode(bBitmap);
                ResultValue = result?.Text;
            }
        }

解析要简单很多：

        private void EncodeToQrCode()
        {
            var qrCodeWriter = new QRCodeWriter();
            var result = qrCodeWriter.encode(Value, BarcodeFormat.QR_CODE, 200, 200);
            var barcodeWriter = new BarcodeWriter();
            using (var bitmap = barcodeWriter.Write(result))
            {
                QrCodeSource = null;
                QrCodeSource = Imaging.CreateBitmapSourceFromHBitmap(bitmap.GetHbitmap(), IntPtr.Zero, Int32Rect.Empty,
                    BitmapSizeOptions.FromEmptyOptions());
            }
        }

ImageSource到Bitmap的转换：

        public static Bitmap BitmapSourceToBitmap(BitmapSource bitmapImage)
        {
            using (var outStream = new MemoryStream())
            {
                BitmapEncoder enc = new BmpBitmapEncoder();
                enc.Frames.Add(BitmapFrame.Create(bitmapImage));
                enc.Save(outStream);
                return new Bitmap(outStream);
            }
        }

 存在内存泄漏问题。