SpeechSynthesisErrorEvent

The charIndex read-only property of the SpeechSynthesisUtterance interface returns the index position of the character in SpeechSynthesisUtterance.text that was being spoken when the event was triggered.

The read-only charLength property of the SpeechSynthesisEvent interface returns the number of characters left to be spoken after the character at the SpeechSynthesisEvent.charIndex position.

The elapsedTime read-only property of the SpeechSynthesisEvent returns the elapsed time in seconds, after the SpeechSynthesisUtterance.text started being spoken, at which the event was triggered.

The error property of the SpeechSynthesisErrorEvent interface returns an error code indicating what has gone wrong with a speech synthesis attempt.

The name read-only property of the SpeechSynthesisUtterance interface returns the name associated with certain types of events occurring as the SpeechSynthesisUtterance.text is being spoken: the name of the SSML marker reached in the case of a SpeechSynthesisUtterance.mark_event event, or the type of boundary reached in the case of a SpeechSynthesisUtterance.boundary_event event.

The utterance read-only property of the SpeechSynthesisUtterance interface returns the SpeechSynthesisUtterance instance that the event was triggered on.