SpeechRecognitionEngine.SetInputToDefaultAudioDevice Method

Definition

Configures the SpeechRecognitionEngine object to receive input from the default audio device.

public:
 void SetInputToDefaultAudioDevice();
public void SetInputToDefaultAudioDevice ();
member this.SetInputToDefaultAudioDevice : unit -> unit
Public Sub SetInputToDefaultAudioDevice ()

Examples

The following example shows part of a console application that demonstrates basic speech recognition. The example uses output from the default audio device, performs multiple, asynchronous recognition operations, and exits when a user utters the phrase, "exit".

using System;  
using System.Globalization;  
using System.Speech.Recognition;  
using System.Threading;  

namespace DefaultInput  
{  
  class Program  
  {  
    // Indicate whether asynchronous recognition has finished.  
    static bool completed;  

    static void Main(string[] args)  
    {  
      using (SpeechRecognitionEngine recognizer =  
        new SpeechRecognitionEngine(new CultureInfo("en-US")))  
      {  

        // Create and load the exit grammar.  
        Grammar exitGrammar = new Grammar(new GrammarBuilder("exit"));  
        exitGrammar.Name = "Exit Grammar";  
        recognizer.LoadGrammar(exitGrammar);  

        // Create and load the dictation grammar.  
        Grammar dictation = new DictationGrammar();  
        dictation.Name = "Dictation Grammar";  
        recognizer.LoadGrammar(dictation);  

        // Attach event handlers to the recognizer.  
        recognizer.SpeechRecognized +=  
          new EventHandler<SpeechRecognizedEventArgs>(  
            SpeechRecognizedHandler);  
        recognizer.RecognizeCompleted +=  
          new EventHandler<RecognizeCompletedEventArgs>(  
            RecognizeCompletedHandler);  

        // Assign input to the recognizer.  
        recognizer.SetInputToDefaultAudioDevice();  

        // Begin asynchronous recognition.  
        Console.WriteLine("Starting recognition...");  
        completed = false;  
        recognizer.RecognizeAsync(RecognizeMode.Multiple);  

        // Wait for recognition to finish.  
        while (!completed)  
        {  
          Thread.Sleep(333);  
        }  
        Console.WriteLine("Done.");  
      }  

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

    static void SpeechRecognizedHandler(  
      object sender, SpeechRecognizedEventArgs e)  
    {  
      Console.WriteLine("  Speech recognized:");  
      string grammarName = "<not available>";  
      if (e.Result.Grammar.Name != null &&  
        !e.Result.Grammar.Name.Equals(string.Empty))  
      {  
        grammarName = e.Result.Grammar.Name;  
      }  
      Console.WriteLine("    {0,-17} - {1}",  
        grammarName, e.Result.Text);  

      if (grammarName.Equals("Exit Grammar"))  
      {  
        ((SpeechRecognitionEngine)sender).RecognizeAsyncCancel();  
      }  
    }  

    static void RecognizeCompletedHandler(  
      object sender, RecognizeCompletedEventArgs e)  
    {  
      Console.WriteLine("  Recognition completed.");  
      completed = true;  
    }  
  }  
}  

Applies to

See also