SpeechRecognitionEngine.EmulateRecognizeAsync Method (String)

Asynchronously simulate audio input to the recognition engine with string.

Namespace: Microsoft.Speech.Recognition
Assembly: Microsoft.Speech (in microsoft.speech.dll)




  • inputText
    A string containing text used as an input phrase in place of audio input during recognition emulation.


The EmulateRecognizeAsync methods return void, applications can only obtain results from asynchronous emulation of speech recognition by handling the events that would be produced by the raising of asynchronous emulation event EmulateRecognizeCompleted as well as actual audio input recognition events such as SpeechRecognized.


The completion of asynchronous emulation event EmulateRecognizeCompleted is always generated after the audio input events such as SpeechRecognized.

A RecognizeCompleted event is not generated by the completion of a EmulateRecognizeAsync.

Emulated recognition ignores new lines and extra white space and treats punctuation literally, rather than letting it define phrases.


In the following example, an application obtains text input through a Textbox, and uses it to emulate speech recognition.

private void EmulateTextBox_KeyPress(object sender, KeyPressEventArgs eventArgs) {
    if ((Keys)eventArgs.KeyChar == Keys.Enter) {

// Emulate when Button is pressed in the emulateTextBox.
private void _emulateButton_Click(object sender, EventArgs e) {

Thread Safety

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


Development Platforms

Windows XP Professional with Service Pack 2 (SP2), Windows Server 2003, Windows Vista Ultimate Edition, Windows Vista Business Edition, Windows Vista Enterprise Edition

Target Platforms

See Also


SpeechRecognitionEngine Class
SpeechRecognitionEngine Members
Microsoft.Speech.Recognition Namespace
SpeechRecognitionEngine.EmulateRecognize Method
SpeechRecognitionEngine.EmulateRecognizeAsync Method
SpeechRecognitionEngine.EmulateRecognize Method
SpeechRecognitionEngine.EmulateRecognize Method
SpeechRecognitionEngine.EmulateRecognizeAsync Method
SpeechRecognitionEngine.EmulateRecognizeAsync Method
RecognizedWordUnit Class