Answers for "nodejs socket.io"

install socket.io

npm i socket.io

how to install socket.io to node js

$ npm install socket.io

create a web server node js w socket.io

var app = require('express')();
var http = require('http').createServer(app);
var io = require('socket.io')(http);

app.get('/', (req, res) => {
  // Ran when a GET request to path '/'
  res.sendFile(__dirname + '/index.html');
});

io.on('connection', (socket) => {
  // Ran when a socket connected
});

http.listen(3000, () => {
  // Ran when server is ready to take requestes
});

socket..io

<script src="https://cdn.socket.io/socket.io-3.0.1.min.js"></script>

js socket.emit

const socket = io('ws://localhost:3000');
socket.on('connect', () => {  
  // either with send()  
  socket.send('Hello!');
  // or with emit() and custom event names  
  socket.emit('salutations', 'Hello!', { 'mr': 'john' }, Uint8Array.from([1, 2, 3, 4]));});
// handle the event sent with socket.send()
socket.on('message', data => {
  console.log(data);
});
// handle the event sent with socket.emit()
socket.on('greetings', (elem1, elem2, elem3) => {
  console.log(elem1, elem2, elem3);
});

socket io nodejs

const express = require('express');const app = express();const http = require('http');const server = http.createServer(app);const { Server } = require("socket.io");const io = new Server(server);app.get('/', (req, res) => {  res.sendFile(__dirname + '/index.html');});io.on('connection', (socket) => {  console.log('a user connected');});server.listen(3000, () => {  console.log('listening on *:3000');});