SpeechRecognizer.StateChanged 事件

public:
 event EventHandler<System::Speech::Recognition::StateChangedEventArgs ^> ^ StateChanged;

public event EventHandler<System.Speech.Recognition.StateChangedEventArgs> StateChanged;

member this.StateChanged : EventHandler<System.Speech.Recognition.StateChangedEventArgs> 

Public Custom Event StateChanged As EventHandler(Of StateChangedEventArgs) 

Public Event StateChanged As EventHandler(Of StateChangedEventArgs) 

事件类型

示例

以下示例创建一个共享语音识别器，然后创建两种类型的语法来识别特定单词和接受自由听写。 该示例以异步方式将所有创建的语法加载到识别器。 事件的处理程序 StateChanged 使用 EmulateRecognizeAsync 方法将 Windows 识别置于“侦听”模式。

using System;
using System.Speech.Recognition;

namespace SampleRecognition
{
  class Program
  {
    private static SpeechRecognizer recognizer;
    public static void Main(string[] args)
    {

      // Initialize a shared speech recognition engine.
      recognizer = new SpeechRecognizer();

      // Add a handler for the LoadGrammarCompleted event.
      recognizer.LoadGrammarCompleted += new EventHandler<LoadGrammarCompletedEventArgs>(recognizer_LoadGrammarCompleted);

      // Add a handler for the SpeechRecognized event.
      recognizer.SpeechRecognized += new EventHandler<SpeechRecognizedEventArgs>(recognizer_SpeechRecognized);

      // Add a handler for the StateChanged event.
      recognizer.StateChanged += new EventHandler<StateChangedEventArgs>(recognizer_StateChanged);

      // Create "yesno" grammar.
      Choices yesChoices = new Choices(new string[] { "yes", "yup", "yah}" });
      SemanticResultValue yesValue =
          new SemanticResultValue(yesChoices, (bool)true);
      Choices noChoices = new Choices(new string[] { "no", "nope", "nah" });
      SemanticResultValue noValue = new SemanticResultValue(noChoices, (bool)false);
      SemanticResultKey yesNoKey =
          new SemanticResultKey("yesno", new Choices(new GrammarBuilder[] { yesValue, noValue }));
      Grammar yesnoGrammar = new Grammar(yesNoKey);
      yesnoGrammar.Name = "yesNo";

      // Create "done" grammar.
      Grammar doneGrammar =
        new Grammar(new Choices(new string[] { "done", "exit", "quit", "stop" }));
      doneGrammar.Name = "Done";

      // Create dictation grammar.
      Grammar dictation = new DictationGrammar();
      dictation.Name = "Dictation";

      // Load grammars to the recognizer.
      recognizer.LoadGrammarAsync(yesnoGrammar);
      recognizer.LoadGrammarAsync(doneGrammar);
      recognizer.LoadGrammarAsync(dictation);

      // Keep the console window open.
      Console.ReadLine();
    }

    // Put the shared speech recognizer into "listening" mode.
    static void  recognizer_StateChanged(object sender, StateChangedEventArgs e)
    {
     if (e.RecognizerState != RecognizerState.Stopped)
      {
        recognizer.EmulateRecognizeAsync("Start listening");
      }
    }

    // Write the text of the recognized phrase to the console.
    static void  recognizer_SpeechRecognized(object sender, SpeechRecognizedEventArgs e)
    {
     Console.WriteLine("Grammar({0}): {1}", e.Result.Grammar.Name, e.Result.Text);

      // Add event handler code here.
    }

    // Handle the LoadGrammarCompleted event.
    static void  recognizer_LoadGrammarCompleted(object sender, LoadGrammarCompletedEventArgs e)
    {
     string grammarName = e.Grammar.Name;
      bool grammarLoaded = e.Grammar.Loaded;
      if (e.Error != null)
      {
        Console.WriteLine("LoadGrammar for {0} failed with a {1}.",
        grammarName, e.Error.GetType().Name);
      }

      // Add exception handling code here.
      Console.WriteLine("Grammar {0} {1} loaded.",
      grammarName, (grammarLoaded) ? "is" : "is not");
    }
  }
}

注解

当 Windows 语音识别的状态更改为 或 Stopped 状态时，Listening共享识别器将引发此事件。

若要在事件发生时获取共享识别器的状态，请使用 RecognizerState 关联的 StateChangedEventArgs的 属性。 若要获取共享识别器的当前状态，请使用识别器的 State 属性。

为 StateChanged 事件创建委托时，可以标识将处理该事件的方法。 若要将事件与事件处理程序关联，请将该委托的一个实例添加到事件中。 除非移除了该委托，否则每当发生该事件时就会调用事件处理程序。 有关事件处理程序委托的详细信息，请参阅 事件和委托。

另请参阅

• RecognizerState
• StateChangedEventArgs
• State