ReplacementText Class

Contains originally recognized text replace using speech normalization by a recognition engine.

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

public class ReplacementText
/** @attribute SerializableAttribute() */ 
public class ReplacementText
public class ReplacementText
Not applicable.

Speech normalization is the use of special constructs or symbols to express speech in writing. For example, normalization can replace the spoken words "a dollar and sixteen cents" with "$1.16" in output text.

For example, if an audio input was:

july four at twelve thirty one PM, I bought a one point six kilograms of fish for fourteen dollars and six cents, at the pike market in seattle washington nine eight one two two

The normalized output might be:

July 4 at 12:31 PM, I bough a 1.6 kg of fish for $14.06, at the pike market in Seattle WA 98122

In this case there are five substitutions, each described by an instance of ReplacementText.

Using the ReplacementText object, an application can determine:

Instances of ReplacementText are typically obtained as members of the System.Collections.ObjectModel.Collection object returned by the ReplacementWordUnits property on RecognizedPhrase (or classes which inherit from RecognizedPhrase such as RecognitionResult) when returned text has been normalized.

In the example below, information about a RecognizedPhrase object returned by a recognition engine is displayed to a user interface.

The code where information about each originally recognized phrase replaced by normalization is displayed using ReplacementText instances obtained ReplacementWordUnits is highlighted.

internal static void DisplayBasicPhraseInfo(Label label, RecognizedPhrase result, SpeechRecognizer rec) {
  if (result != null && label != null) {// Blank
    if (rec != null) { //Clear
      label.Text += String.Format(
                                  "  Recognizer currently at:   {0} mSec\n" +
                                  "  Audio Device currently at: {1} mSec\n",
    if (result != null) { //Clear
      RecognitionResult recResult = result as RecognitionResult;
      if (recResult != null) {
        RecognizedAudio resultAudio = recResult.Audio;
        if (resultAudio == null) {
          label.Text += String.Format(
                                      "  Emulated input\n");
        } else {
          label.Text += String.Format(
                                      "  Candidate Phrase at:       {0} mSec\n" +
                                      "  Phrase Length:             {1} mSec\n" +
                                      "  Input State Time:          {2}\n" +
                                      "  Input Format:              {3}\n",
      label.Text += String.Format("  Confidence Level:          {0}\n", result.Confidence);
      if (result.Grammar != null) {
        label.Text += String.Format(
                                    "  Recognizing Grammar:       {0}\n" +
                                    "  Recognizing Rule:          {1}\n",
                                    ((result.Grammar.Name != null) ? (result.Grammar.Name) : "None"),
                                    ((result.Grammar.RuleName != null) ? (result.Grammar.RuleName) : "None"));
            repText=repText.TrimStart();          }          if ((rep.DisplayAttributes & DisplayAttributes.ZeroTrailingSpaces) != 0) {            repText = repText.TrimEnd();           }label.Text+=String.Format("Atindex{0}for{1}words.Text:\"{2}\"\n",rep.FirstWordIndex,rep.CountOfWords,repText);}label.Text+=String.Format("\n\n");}



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

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0

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