windows rt 扫描二维码

项目中使用的是ZXing.net，应用商店程序。使用到的dll是ZXing.winmd。

大致思路为，使用MediaCapture捕获图片。获取到CapturePhotoToStreamAsync流，然后将其转换为WriteableBitmap，使用ZXing进行解析，该项目主要是为了获取二维码类型和文本值。

代码如下：

         private async void CaptureBarcode()
         {
             mediaCapture = new MediaCapture();
             await mediaCapture.InitializeAsync();
             captureElement.Source = mediaCapture;
             await mediaCapture.StartPreviewAsync();
             Result result = default(Result);
             while (true)
             {
                 IRandomAccessStream stream = new InMemoryRandomAccessStream();
                 await mediaCapture.CapturePhotoToStreamAsync(ImageEncodingProperties.CreatePng(), stream);
                 await stream.FlushAsync();
                 stream.Seek();
                 IBarcodeReader reader = new BarcodeReader();
                 WriteableBitmap bitmap = new WriteableBitmap(, );
                 bitmap.SetSource(stream);
                 if (bitmap == null)
                     continue;
                 result = reader.Decode(bitmap);
                 if (result != null)
                     break;
                 continue;
             }
             if (result == default(Result))
                 return;
             await mediaCapture.StopPreviewAsync();
             jsonFunc("{ \"type\":\"" + result.BarcodeFormat + "\",\"code\":\"" + result.Text + "\"}");
         }