You can check if a WebSocket
is disconnected by doing either of the following:
- Specifying a function to the
WebSocket.onclose
event handler property, or; - Using
addEventListener
to listen to theclose
event.
In either case, CloseEvent
is passed to the event handler.
For example, you would use the event handler property like so:
const ws = new WebSocket('ws://localhost:8080'); ws.onclose = function (event) { console.log('disconnected'); };
Or, as an alternative, you could use addEventListener
(to listen to the close
event) like so:
const ws = new WebSocket('ws://localhost:8080'); ws.addEventListener('close', function (event) { console.log('disconnected'); });
The close
event is fired when the connection with a WebSocket
is closed. When this happens, the readyState
of the WebSocket
connection changes to CLOSED
.
This post was published by Daniyal Hamid. Daniyal currently works as the Head of Engineering in Germany and has 20+ years of experience in software engineering, design and marketing. Please show your love and support by sharing this post.