语音识别器中的异步等待

Question

我正在尝试通过以下更改复制 this 示例：

使用控制台应用程序而不是 Windows：这看起来没问题，因为计算机正在跟我说话
使用 Sync 功能：看起来我弄错了。

更新程序执行后，它会跟我说话，并等待按键被按下，之后它等待 'listening' 但 sre_SpeechRecognized 没有执行。

下面是我的代码，谢谢：

using System;
using System.Threading.Tasks;
using System.Speech.Synthesis;
using System.Speech.Recognition;

class Startup {
        // Create a simple handler for the SpeechRecognized event
    static void sre_SpeechRecognized (object sender, SpeechRecognizedEventArgs e)
    {
        string speech = e.Result.Text;

                //handle custom commands
        switch (speech)
        {
            case "red":
                Console.WriteLine("Hello");
                break;
            case "green":
                System.Diagnostics.Process.Start("Notepad");
                break;
            case "blue":
                Console.WriteLine("You said blue");
                break;
            case "Close":
               Console.WriteLine("Speech recognized: {0}", e.Result.Text);
                break;
        }
        Console.WriteLine("Speech recognized: {0}", e.Result.Text);
    }

public async Task<object> Invoke(dynamic i) {
// Initialize a new instance of the SpeechSynthesizer.
        SpeechSynthesizer synth = new SpeechSynthesizer();

        // Configure the audio output. 
        synth.SetOutputToDefaultAudioDevice();

        // Speak a string.
        synth.Speak("This example demonstrates a basic use of Speech Synthesizer");

        Console.WriteLine();
        Console.WriteLine("Press any key to exit...");
        Console.ReadKey();

        // Create a new SpeechRecognitionEngine instance.
        SpeechRecognizer recognizer = new SpeechRecognizer();

        // Create a simple grammar that recognizes "red", "green", or "blue".
        Choices colors = new Choices();
        colors.Add(new string[] { "red", "green", "blue" });

        // Create a GrammarBuilder object and append the Choices object.
        GrammarBuilder gb = new GrammarBuilder();
        gb.Append(colors);

        // Create the Grammar instance and load it into the speech recognition engine.
        Grammar g = new Grammar(gb);
        recognizer.LoadGrammar(g);

        // Register a handler for the SpeechRecognized event.
        recognizer.SpeechRecognized += 
          new EventHandler<SpeechRecognizedEventArgs> (Startup.sre_SpeechRecognized);
       Console.WriteLine("Exiting now..");
   return null;
}
}

Answer 1

你没有启动识别。请查看您发布的 link。在示例中注册事件后，有一行 sre.Recognize(); （您的代码中缺少该行）。还有一个方法RecognizeAsync()提到了，这可能是你想要的。

Answer 2

修改Invoke方法如下（这是Async调用者（此处为Node Js）等待Synchronous事件完成的典型情况）

重要细节（请注意此修改的基础是语音引擎按预期工作）

将 Invoke 方法改为 Sync，而不是 Async，因为原始代码中没有 Async 调用
将 return 值替换为任务以获取事件 return 值
使事件内联以便于使用对象
最后添加Recognize同步方法

Will return 当 Task 完成 post 事件触发并将结果包含在 Task<string> 中，可以使用 TaskObject.Result 属性

  public async Task<object> Invoke(dynamic i) {    // async here is required to be used by Edge.JS that is a node.js module enable communicating with C# files
  var tcs = new TaskCompletionSource<object>();
  // Initialize a new instance of the SpeechSynthesizer.
    SpeechSynthesizer synth = new SpeechSynthesizer();

    // Configure the audio output. 
    synth.SetOutputToDefaultAudioDevice();

    // Speak a string.
    synth.Speak("This example demonstrates a basic use of Speech Synthesizer");

    Console.WriteLine();
    Console.WriteLine("Press any key to exit...");
    Console.ReadKey();

    // Create a new SpeechRecognitionEngine instance.

    SpeechRecognitionEngine recognizer = new SpeechRecognitionEngine();

    recognizer.SetInputToDefaultAudioDevice();

    // Create a simple grammar that recognizes "red", "green", or "blue".
    Choices colors = new Choices();
    colors.Add(new string[] { "red", "green", "blue" });

    // Create a GrammarBuilder object and append the Choices object.
    GrammarBuilder gb = new GrammarBuilder();
    gb.Append(colors);

    // Create the Grammar instance and load it into the speech recognition engine.
    Grammar g = new Grammar(gb);
    recognizer.LoadGrammar(g);

    // Register a handler for the SpeechRecognized event.
    recognizer.SpeechRecognized += (sender,e) => {

       string speech = e.Result.Text;

        //handle custom commands
        switch (speech)
        {
            case "red":
             tcs.SetResult("Hello Red");
            break;
            case "green":
             tcs.SetResult("Hello Green");
            break;
            case "blue":
             tcs.SetResult("Hello Blue");
             break;
            case "Close":
             tcs.SetResult("Hello Close");
            break;
           default:
             tcs.SetResult("Hello Not Sure");
          break;
}

 };

   // For Edge JS we cannot await an Async Call (else it leads to error)
   recognizer.Recognize();              
   return tcs.Task.Result;

   //// For pure C#
   // await recognizer.RecognizeAsync();              
   // return tcs.Task;
}

异步特定更改

public async Task<object> Invoke(dynamic i)（制作方法 async 和 return 类型 Task，异步方法的要求）
调用await recognizer.RecognizeAsync();（调用等待异步调用）
return tcs.Task（return类型需要是Task）

语音识别器中的异步等待

async wait in Speech recognizer

c#

speech-recognition

async-await