run node js code example

Example 1: nodejs hello world

const http = require('http');

const hostname = '127.0.0.1';
const port = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello World');
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

Example 2: node js server

const express = require('express')
const app = express()
const port = 3000

app.get('/', (req, res) => res.send('Hello World!'))

app.listen(port, () => console.log(`Example app listening at http://localhost:${port}`))

Example 3: run node js

node name_app.js

Example 4: node run command

// Run a command asynchronously
const { spawn } = require('child_process');
const dir = spawn('cmd', ['/c', 'dir']);

dir.stdout.on('data', data => console.log(`Stdout: ${data}`));
dir.stderr.on('data', data => console.log(`Stderr: ${data}`));
dir.on('close', code => console.log(`Exit code: ${code}`));

// Run a command synchronously
const { spawnSync } = require( 'child_process' );
const dir = spawnSync('cmd', ['/c', 'dir']);

console.log(`Stdout: ${dir.stdout.toString()}`);
console.log(`Stderr: ${dir.stderr.toString()}`);

Example 5: create node project

#1. server.js
var express = require('express');
var app = express();

app.get('/', function (req, res) {
  res.status(200).send('Hello World!');
});

var port = process.env.PORT || 3000;

var server = app.listen(port, function() {
  console.log('Express server listening on port ' + port);
});

open cmd run server.js
"node server.js"
log:Express server listening on port 3000

& then

open link "http://localhost:3000/" in your browser and show result.

Example 6: how to run a js file in node

Save your .js file in the same folder as node.js,
For windows , Usually location is- "C:\Program Files\nodejs"
Open 'Command prompt and locate node.js folder' OR directly open 'Node.js command prompt' and type 
>> node (file_name).js