事件处理程序 C# 和 TextBlock

Question

我是新来的，是c#。我正在尝试使用 c# 使用网络上的示例代码通过 Raspberry 进行语音识别。当我从方法调用TextBlock.Text时，我的程序崩溃。也许是因为这是一个事件处理程序。我该如何解决这个问题？如果我在程序的另一个点（不用作事件处理程序的方法）中使用这三行代码，它可以工作。抱歉，我是新手，我不知道这种语言是如何工作的，如果您可以更正代码，我会更好地理解它。

namespace RPiVoice
{
    public sealed partial class MainPage : Page
    {
        private const int RED_LED_PIN = 5;
        ...
        public MainPage()
        {
            this.InitializeComponent();
            Unloaded += MainPage_Unload
            initializeSpeechRecognizer();
            initializeGPIO();
        }
        private void initializeGPIO()
        {
                      gpio = GpioController.GetDefault();
            // // Initialize GPIO Pins
            redPin = gpio.OpenPin(RED_LED_PIN);
            greenPin = gpio.OpenPin(GREEN_LED_PIN);
            bedroomLightPin = gpio.OpenPin(BEDROOM_LIGHT_PIN);
            redPin.SetDriveMode(GpioPinDriveMode.Output);
            greenPin.SetDriveMode(GpioPinDriveMode.Output);
            bedroomLightPin.SetDriveMode(GpioPinDriveMode.Output);
            // Write low initially, this step is not needed
            redPin.Write(GpioPinValue.Low);
            greenPin.Write(GpioPinValue.Low);
            bedroomLightPin.Write(GpioPinValue.Low);
        }
        // Initialize Speech Recognizer and start async recognition
        private async void initializeSpeechRecognizer()
        {
            // Initialize recognizer
            var recognizer = new SpeechRecognizer(new Windows.Globalization.Language("it-IT"));
            // Set event handlers -> the problem should be here
            recognizer.StateChanged += RecognizerStateChanged;
            recognizer.ContinuousRecognitionSession.ResultGenerated += RecognizerResultGenerated;
        }
        // Recognizer generated results
        private async void RecognizerResultGenerated(SpeechContinuousRecognitionSession session, SpeechContinuousRecognitionResultGeneratedEventArgs args)
        {
            ...

                    await Window.Current.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, async () => {
                        this.Stato.Text = "test"; //this make the program crash!
                    });
                };
}

Answer 1

我相信

您需要调用在其中创建文本框的线程。因此，应将其写为：

this.Dispatcher.Invoke((Action)(() =>
{
        this.Stato.Text = "test";
}));

而不是：

                await Window.Current.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, async () => {
                    this.Stato.Text = "test"; //this make the program crash!
                });