SpeechRecognizer.StateChanged 事件

定义

当 Windows“桌面语音技术”识别引擎的运行状态更改时发生。

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

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。

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

适用于

产品 版本
.NET 8 (package-provided), 9 (package-provided)
.NET Framework 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7 (package-provided), 4.7, 4.7.1 (package-provided), 4.7.1, 4.7.2 (package-provided), 4.7.2, 4.8 (package-provided), 4.8, 4.8.1
.NET Standard 2.0 (package-provided)

另请参阅