RTCDataChannel: close() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.

The RTCDataChannel.close() method closes the RTCDataChannel. Either peer is permitted to call this method to initiate closure of the channel.

Closure of the data channel is not instantaneous. Most of the process of closing the connection is handled asynchronously; you can detect when the channel has finished closing by watching for a close event on the data channel.

The sequence of events which occurs in response to this method being called:

  1. RTCDataChannel.readyState is set to closing.
  2. A background task is established to handle the remainder of the steps below, and close() returns to the caller.
  3. The transport layer deals with any buffered messages; the protocol layer decides whether to send them or discard them.
  4. The underlying data transport is closed.
  5. The RTCDataChannel.readyState property is set to closed.
  6. If the transport was closed with an error, the RTCDataChannel is sent an error event with its name set to NetworkError.
  7. A close event is sent to the channel.

Syntax

js
close()

Parameters

None.

Return value

None (undefined).

Examples

js
const pc = new RTCPeerConnection();
const dc = pc.createDataChannel("my channel");

dc.onmessage = (event) => {
  console.log(`received: ${event.data}`);
  dc.close(); // We decided to close after the first received message
};

dc.onopen = () => {
  console.log("datachannel open");
};

dc.onclose = () => {
  console.log("datachannel close");
};

// Now negotiate the connection and so forth…

Specifications

Specification
WebRTC: Real-Time Communication in Browsers
# dom-rtcdatachannel-close

Browser compatibility

See also