A datachannel event is sent to an RTCPeerConnection instance when an RTCDataChannel has been added to the connection, as a result of the remote peer calling RTCPeerConnection.createDataChannel().

This event is not cancelable and does not bubble.

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("datachannel", (event) => {});

ondatachannel = (event) => {};

An RTCDataChannelEvent. Inherits from Event.

Also inherits properties from Event.

channel Read only

Returns the RTCDataChannel associated with the event.

This example sets up a function that handles datachannel events by gathering the information needed to communicate with the newly added RTCDataChannel and by adding event handlers for the events that occur on that channel.

pc.addEventListener(
  "datachannel",
  (ev) => {
    receiveChannel = ev.channel;
    receiveChannel.onmessage = myHandleMessage;
    receiveChannel.onopen = myHandleOpen;
    receiveChannel.onclose = myHandleClose;
  },
  false,
);

receiveChannel is set to the value of the event's channel property, which specifies the RTCDataChannel object representing the data channel linking the remote peer to the local one.

This same code can also instead use the RTCPeerConnection interface's ondatachannel event handler property, like this:

pc.ondatachannel = (ev) => {
  receiveChannel = ev.channel;
  receiveChannel.onmessage = myHandleMessage;
  receiveChannel.onopen = myHandleOpen;
  receiveChannel.onclose = myHandleClose;
};

• WebRTC API
• Using WebRTC data channels
• A simple RTCDataChannel sample
• RTCDataChannelEvent
• RTCPeerConnection.createDataChannel()