RTCDataChannel.onmessage

The RTCDataChannel.ommessage property stores an EventHandler which specifies a function to be called when the message event is fired on the channel. This event is represented by the MessageEvent interface. This event is sent to the channel when a message is received from the other peer.

Syntax

RTCDataChannel.onmessage = function;

Value

A function which the browser will call to handle the message event. The function receives as its sole input parameter a MessageEvent object describing the event.

Example

This code snippet creates a peer connection, adds a data channel to it, and starts creating new <p> (paragraph) elements each time a message arrives, with the message's contents displayed inside it. The new elements are then attached to the end of the document.

let pc = new RTCPeerConnection();
let dc = pc.createDataChannel();

dc.onmessage = function(event) {
  var el = document.createElement("p");
  var txtNode = document.createTextNode(event.data);
 
  el.appendChild(txtNode);
  receiveBox.appendChild(el);
}

Specifications

Browser compatibility

[1] The interface is called DataChannel and not RTCDataChannel in Firefox. However, a binding has been in place since Firefox 24 so that either name will work.

[2] WebRTC, including RTCDataChannel, was introduced in Chrome 28 for Android behind a flag, and enabled by default starting in Chrome 29 for Android.

See also

• WebRTC
• RTCPeerConnection
• RTCDataChannel
• The message event and its type, MessageEvent.