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NodeJS Socket io communication

"Hello world!" with socket messages

Install node modules

npm install express
npm install

Node.js server

const express = require('express');
const app = express();
const server = app.listen(3000,console.log(" Hello World server started!"));
const io = require('')(server);
io.on('connection', (socket) => {
 //console.log("Client connected!");
 socket.on('message-from-client-to-server', (msg) => {
 socket.emit('message-from-server-to-client', 'Hello World!');

Browser client

<!DOCTYPE html>
<html lang="en">
 <meta charset="UTF-8">
 <title>Hello World with</title>
 <script src=""></script>
 var socket = io("http://localhost:3000");
 socket.on("message-from-server-to-client", function(msg) {
 document.getElementById('message').innerHTML = msg;
 socket.emit('message-from-client-to-server', 'Hello World!');
 <p> Hello World client started!</p>
 <p id="message"></p>


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