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SemanticResultKey Class

Definition

Associates a key string with SemanticResultValue values to define SemanticValue objects.

public ref class SemanticResultKey
public class SemanticResultKey
type SemanticResultKey = class
Public Class SemanticResultKey
Inheritance
SemanticResultKey

Examples

The following example creates a Grammar to recognize password input of the form "My password is …", where the actual input is matched with a wildcard.

The wildcard is tagged with a semantic key, and the SpeechRecognized handler checks for the presence of this tag to verify that a password input has occurred.

private void pwdGrammar()
{
  GrammarBuilder pwdBuilder = new GrammarBuilder("My Password is");
  GrammarBuilder wildcardBuilder = new GrammarBuilder();
  wildcardBuilder.AppendWildcard();
  SemanticResultKey wildcardKey= new SemanticResultKey("Password", wildcardBuilder);
  pwdBuilder+=wildcardKey;
  Grammar grammar = new Grammar(pwdBuilder);
  grammar.Name = "Password input";

  grammar.SpeechRecognized += delegate(object sender, SpeechRecognizedEventArgs eventArgs)
  {
    SemanticValue semantics = eventArgs.Result.Semantics;
    RecognitionResult result=eventArgs.Result;

    if (!semantics.ContainsKey("Password"))
    {
      SpeechUI.SendTextFeedback(eventArgs.Result, "No Password Provided", false);
    }
    else
    {
      RecognizedAudio pwdAudio = result.GetAudioForWordRange(result.Words[3], result.Words[result.Words.Count - 1]);
      MemoryStream pwdMemoryStream = new MemoryStream();
      pwdAudio.WriteToAudioStream(pwdMemoryStream);
      if (!IsValidPwd(pwdMemoryStream))
      {
        string badPwd = System.IO.Path.GetTempPath() + "BadPwd" + (new Random()).Next().ToString() + ".wav";
        FileStream waveStream = new FileStream(badPwd, FileMode.Create);
        pwdAudio.WriteToWaveStream(waveStream);
        waveStream.Flush();
        waveStream.Close();
        SpeechUI.SendTextFeedback(eventArgs.Result, "Invalid Password", false);

      }
    }
  };
  grammar.Enabled = true;
  _recognizer.LoadGrammar(grammar);
  UpdateGrammarTree(_grammarTreeView, _recognizer);

}

Remarks

The basic unit of semantic expression in System.Speech is the SemanticValue, which is a key/value pair.

Using SemanticResultKey objects, you tag SemanticResultValue instances contained in GrammarBuilder objects and strings so that the values may readily be accessed from SemanticValue instances on recognition.

You can use SemanticResultValue and SemanticResultKey objects, in conjunction with GrammarBuilder and Choices objects, to define the semantic structure for a speech recognition grammar. To access the semantic information in a recognition result, obtain an instance of SemanticValue through the Semantics property on RecognizedPhrase.

Constructors

SemanticResultKey(String, GrammarBuilder[])

Assigns a semantic key to one or more GrammarBuilder objects used to create a speech recognition grammar.

SemanticResultKey(String, String[])

Assigns a semantic key to one or more String instances used to create a speech recognition grammar.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToGrammarBuilder()

Returns an instance of GrammarBuilder constructed from the current SemanticResultKey instance.

ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also