以下代码不起作用

Question

我从这里复制了以下代码： https://code.msdn.microsoft.com/windowsapps/WindowsPhone-Store-81-vs-25c80c2a#content

MediaCapture captureManager;
    async private void InitCamera_Click(object sender, RoutedEventArgs e)
    {
        captureManager = new MediaCapture();
        await captureManager.InitializeAsync();
    }

    async private void StartCapturePreview_Click(object sender, RoutedEventArgs e)
    {
        capturePreview.Source = captureManager;
        await captureManager.StartPreviewAsync();
    }

    async private void StopCapturePreview_Click(object sender, RoutedEventArgs e)
    {
        await captureManager.StopPreviewAsync();
    }

    async private void CapturePhoto_Click(object sender, RoutedEventArgs e)
    {
        ImageEncodingProperties imgFormat = ImageEncodingProperties.CreateJpeg();

        // create storage file in local app storage 
        StorageFile file = await ApplicationData.Current.LocalFolder.CreateFileAsync(
            "TestPhoto.jpg",
            CreationCollisionOption.GenerateUniqueName);

        // take photo 
        await captureManager.CapturePhotoToStorageFileAsync(imgFormat, file);

        // Get photo as a BitmapImage 
        BitmapImage bmpImage = new BitmapImage(new Uri(file.Path));

        // imagePreivew is a <Image> object defined in XAML 
        imagePreview.Source = bmpImage;
    }

当我尝试运行时，它没有定义 capturePreview。我删除了该行，但出现两个异常：

Exception thrown: 'System.ArgumentException' in mscorlib.ni.dll

Exception thrown: 'System.ArgumentException' in mscorlib.ni.dll

你知道问题所在吗？ Windows phone 8.1 RT 应用程序

编辑：同样的代码也可以在这里找到：https://msdn.microsoft.com/en-us/library/windows.media.capture.mediacapture.aspx?f=255&MSPPError=-2147217396

Answer 1

我在另一个页面中遇到异常，当我调用此框架时出现异常，这与实际代码无关。

以下代码不起作用

The following code doesnt work

c#

camera

capture

windows-phone-8.1