Web/API/RTCDTMFToneChangeEvent

The RTCDTMFToneChangeEvent interface represents events sent to indicate that DTMF tones have started or finished playing. This interface is used by the tonechange event.

Properties

In addition to the properties of Event, this interface offers the following:

RTCDTMFToneChangeEvent.tone Read only: A DOMString specifying the tone which has begun playing, or an empty string ("") if the previous tone has finished playing.

Constructors

RTCDTMFToneChangeEvent(): Returns a new RTCDTMFToneChangeEvent. It takes two parameters, the first being a DOMString representing the type of the event (always "tonechange"); the second a dictionary containing the initial state of the properties of the event.

Methods

Supports the methods defined in Event. There are no additional methods.

Examples

This snippet is derived loosely from the full, working example you'll find in When a tone finishes playing in Using DTMF with WebRTC. It appends each tone to a display box as it's played, and, once all tones have been sent, re-enabled a previously-disabled "Send" button, allowing the next DMTF string to be entered.

dtmfSender.addEventListener("change", function(event) {
  if (event.tone !== "") {
    dialStringBox.innerText += event.tone;
  } else {
    sendDTMFButton.disabled = false;
  }
}, false);

Specifications

Specification	Status	Comment
WebRTC 1.0: Real-time Communication Between BrowsersThe definition of 'RTCDTMFToneChangeEvent' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`RTCDTMFToneChangeEvent`	Chrome Full support 27	Edge Full support 12	Firefox Full support 52	IE No support No	Opera Full support Yes	Safari ?	WebView Android Full support 4.4	Chrome Android Full support 27	Firefox Android Full support 52	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support 1.5
`RTCDTMFToneChangeEvent()` constructor	Chrome Full support 27	Edge Full support ≤18	Firefox Full support 52	IE No support No	Opera Full support Yes	Safari ?	WebView Android Full support 4.4	Chrome Android Full support 27	Firefox Android Full support 52	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support 1.5
`tone`	Chrome Full support 27	Edge Full support 12	Firefox Full support 52	IE No support No	Opera Full support Yes	Safari ?	WebView Android Full support 4.4	Chrome Android Full support 27	Firefox Android Full support 52	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support 1.5

Legend

Full support: Full support
No support: No support
Compatibility unknown: Compatibility unknown