How to detect that a socket.io user has disconnected?

Question

Node.js

Is there any way to know that the user has disconnected, for example by closing the browser or tab?
It is clear that you can periodically send a request and check for a response. But does socket.io itself have a ready-made solution, like io.on('connection'..., only on disconnect?

Answer 1

You answered your own question.

io.on('connection', socket => {
  socket.on('disconnect', () => {
    // ваш код
  })
})

Everything is written in the documentation socket.io/docs