SpeechSynthesisEvent

{{APIRef("Web Speech API")}}

The SpeechSynthesisEvent interface of the Web Speech API contains information about the current state of {{domxref("SpeechSynthesisUtterance")}} objects that have been processed in the speech service.

{{InheritanceDiagram}}

Constructor

• {{domxref("SpeechSynthesisEvent.SpeechSynthesisEvent", "SpeechSynthesisEvent()")}}
  • : Creates a new SpeechSynthesisEvent.

Instance properties

The SpeechSynthesisEvent interface also inherits properties from its parent interface, {{domxref("Event")}}.

• {{domxref("SpeechSynthesisEvent.charIndex")}} {{ReadOnlyInline}}
  • : Returns the index position of the character in the {{domxref("SpeechSynthesisUtterance.text")}} that was being spoken when the event was triggered.
• {{domxref("SpeechSynthesisEvent.charLength")}} {{ReadOnlyInline}}
  • : Returns the number of characters left to be spoken after the charIndex position, if the speaking engine supports it. Returns 0 if the speaking engine can't provide the information.
• {{domxref("SpeechSynthesisEvent.elapsedTime")}} {{ReadOnlyInline}}
  • : Returns the elapsed time in seconds after the {{domxref("SpeechSynthesisUtterance.text")}} started being spoken that the event was triggered at.
• {{domxref("SpeechSynthesisEvent.name")}} {{ReadOnlyInline}}
  • : Returns the name associated with certain types of events occurring as the {{domxref("SpeechSynthesisUtterance.text")}} is being spoken: the name of the SSML marker reached in the case of a {{domxref("SpeechSynthesisUtterance.mark_event", "mark")}} event, or the type of boundary reached in the case of a {{domxref("SpeechSynthesisUtterance.boundary_event", "boundary")}} event.
• {{domxref("SpeechSynthesisEvent.utterance")}} {{ReadOnlyInline}}
  • : Returns the {{domxref("SpeechSynthesisUtterance")}} instance that the event was triggered on.

Instance methods

The SpeechSynthesisEvent interface also inherits methods from its parent interface, {{domxref("Event")}}.

Examples

utterThis.onpause = (event) => {
  const char = event.utterance.text.charAt(event.charIndex);
  console.log(
    `Speech paused at character ${event.charIndex} of "${event.utterance.text}", which is "${char}".`,
  );
};

utterThis.onboundary = (event) => {
  console.log(
    `${event.name} boundary reached after ${event.elapsedTime} seconds.`,
  );
};

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• Web Speech API