WebSocket: close event

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Note: This feature is available in Web Workers.

The close event is fired when a connection with a WebSocket is closed.

Syntax

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

js
addEventListener("close", (event) => { })

onclose = (event) => { }

Event type

A CloseEvent. Inherits from Event.

Event CloseEvent

Examples

You might want to know when the connection has been closed so that you can update the UI or, perhaps, save data about the closed connection. Given that you have a variable called exampleSocket that refers to an opened WebSocket, this handler would handle the situation where the socket has been closed.

js
exampleSocket.addEventListener("close", (event) => {
  console.log("The connection has been closed successfully.");
});

You can perform the same actions using the event handler property, like this:

js
exampleSocket.onclose = (event) => {
  console.log("The connection has been closed successfully.");
};

Specifications

Specification
WebSockets
# dom-websocket-onclose

Browser compatibility

See also