RTCDataChannel.onclose

The RTCDataChannel.onclose property is an event handler which specifies a function to be called by the browser when the close event is received by the RTCDataChannel. This is a simple Event which indicates that the data channel has closed down.

A function which the browser will call to handle the close event. The function receives as its sole input parameter the event itself, as an object of type Event.

In this sample from a hypothetical instant messaging client, a data channel is created, then handlers for the open and close events are set up to enable and disable user interface objects based on the state of the channel. This way, the message entry field and the send button are only enabled for use when the connection is actually open.

let pc = new RTCPeerConnection();
let dc = pc.createDataChannel("MessageChannel")}};

dc.onopen = function(event) {
  document.getElementById("messageBox").disabled = false;
  document.getElementById("sendButton").disabled = false;
};

dc.onclose = function(event) {
  document.getElementById("messageBox").disabled = true;
  document.getElementById("sendButton").disabled = true;
}

/* Now negotiate the connection, etc... */

• WebRTC
• The close event and its type, Event.
• RTCDataChannel.onopen
• The open event and its type, Event.