RecognizedWordUnit Class


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Provides the atomic unit of recognized speech.

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


Public Class RecognizedWordUnit


Gets a value, assigned by the recognizer, that represents the likelihood that a recognized word matches a given input.


Gets formatting information used to create the text output from the current RecognizedWordUnit instance.


Gets the unnormalized text of a recognized word.


Gets the phonetic spelling of a recognized word.


Gets the normalized text for a recognized word.


Determines whether the specified object is equal to the current object.(Inherited from Object.)


Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Creates a shallow copy of the current Object.(Inherited from Object.)


Returns a string that represents the current object.(Inherited from Object.)

All results returned by a recognition engine are constructed of RecognizedWordUnit objects.

An array of RecognizedWordUnit objects is accessible for any recognition operation through the Words property on the RecognizedPhrase object.

In addition to providing a measure of recognition certainty (Confidence) a RecognizedWordUnit instance provides:

  • Normalized and exact (or lexical) text representations for a recognized word. For more information, see ReplacementText, Text, and LexicalForm.

  • Pronunciation information using characters from a supported phonetic alphabet, such as the International Phonetic Alphabet (IPA) or the Universal Phone Set (UPS). For more information see Pronunciation.

  • Formatting for printing. For more information see the DisplayAttributes class and its DisplayAttributes property.

The following example shows a utility routine (stringFromWordArray) that generates strings. The strings contain lexical output (using LexicalForm), normalized text (using Text), or phonetic characters from the International Phonetic Alphabet (using Pronunciation). Strings are formatted using DisplayAttributes objects obtained from the DisplayAttributes property from a ReadOnlyCollection(Of T) of RecognizedWordUnit objects. The RecognizedWordUnit objects are obtained from the Words property on the RecognizedPhrase object.

internal enum WordType 
  Normalized = Text,
internal static string stringFromWordArray(ReadOnlyCollection<RecognizedWordUnit> words, WordType type) 
  string text = "";
  foreach (RecognizedWordUnit word in words) 
    string wordText = "";
    if (type == WordType.Text || type == WordType.Normalized) 
      wordText = word.Text;
    else if (type == WordType.Lexical) 
      wordText = word.LexicalForm;
    else if (type == WordType.Pronunciation) 
      wordText = word.Pronunciation;
      throw new InvalidEnumArgumentException(String.Format("[0}: is not a valid input", type));
    // Use display attribute

    if ((word.DisplayAttributes & DisplayAttributes.OneTrailingSpace) != 0) 
      wordText += " ";
    if ((word.DisplayAttributes & DisplayAttributes.TwoTrailingSpaces) != 0)
      wordText += "  ";
    if ((word.DisplayAttributes & DisplayAttributes.ConsumeLeadingSpaces) != 0) 
      wordText = wordText.TrimStart();
    if ((word.DisplayAttributes & DisplayAttributes.ZeroTrailingSpaces) != 0)
      wordText = wordText.TrimEnd();

    text += wordText;

  return text;

.NET Framework
Available since 3.0

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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