SemanticResultKey.ToGrammarBuilder Method ()


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

Namespace:   System.Speech.Recognition
Assembly:  System.Speech (in System.Speech.dll)

public GrammarBuilder ToGrammarBuilder()

The use of ToGrammarBuilder is equivalent to using the GrammarBuilder constructor which takes SemanticResultKey as an argument (GrammarBuilder(SemanticResultKey)).

The following example creates a Grammar object that supports commands to change the background color.

A Choices object (colorChoice) containing the list of options for background colors is filled using the Add(GrammarBuilder[]) method with GrammarBuilder instances. The GrammarBuilder instances are obtained through the ToGrammarBuilder() method on the SemanticResultValue objects created from color strings.

A GrammarBuilder is then obtained by calling ToGrammarBuilder() on a SemanticResultKey instance, which will be used to key the semantic choices in colorChoice.

private Grammar CreateGrammarBuilderRGBSemantics() 

  // Create a set of choices, each a lookup from a color name to RGB.
  // Choices constructors do not take SemanticResultValue parameters, so cast 
  // the SemanticResultValue to GrammarBuilder.
  Choices colorChoice = new Choices();
  foreach (string colorName in System.Enum.GetNames(typeof(KnownColor))) 
    SemanticResultValue colorValue=new SemanticResultValue(colorName, Color.FromName(colorName).ToArgb());

    // Use implicit conversion of SemanticResultValue to GrammarBuilder.
  SemanticResultKey choiceKey = new SemanticResultKey("rgb", colorChoice);
  GrammarBuilder choiceBuilder = choiceKey.ToGrammarBuilder();

  // Create two intermediate grammars with introductory phrase and the color choice.
  GrammarBuilder makeBackgroundBuilder = "Make background";

  GrammarBuilder configureBackgroundBuilder = new GrammarBuilder("Configure background as");
  configureBackgroundBuilder.Append((new SemanticResultKey("rgb", colorChoice)).ToGrammarBuilder());

  // Create the Grammar object, which recognizes either intermediate grammar.
  Grammar grammar = new Grammar(new Choices(new GrammarBuilder[] {makeBackgroundBuilder, configureBackgroundBuilder}));
  grammar.Name = "Make Background /Configure background as";

  return grammar;

.NET Framework
Available since 3.0
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