Example 1: express.js server
/* ====== create node.js server with express.js framework ====== */
// dependencies
const express = require("express");
const app = express();
app.get("/", (req, res) => {
res.send("This is home page.");
});
app.post("/", (req, res) => {
res.send("This is home page with post request.");
});
// PORT
const PORT = 3000;
app.listen(PORT, () => {
console.log(`Server is running on PORT: ${PORT}`);
});
// ======== Instructions ========
// save this as index.js
// you have to download and install node.js on your machine
// open terminal or command prompt
// type node index.js
// find your server at http://localhost:3000
Example 2: express hello world
//to run : node filename.js
const express = require('express')
const app = express()
const port = 3000
app.get('/', (req, res) => res.send('Hello World!'))
app.listen(port, () => console.log(`Example app listening at http://localhost:${port}`))
//visit localhost:3000
// assuming you have done 1) npm init 2) npm install express
Example 3: how to make an express server
// this is your code
// ZDev1
// first you should install express in the terminal
// `npm i express`.
const express = require('express');
const app = express();
// route
app.get('/', (req,res)=>{
// Sending This is the home page! in the page
res.send('This is the home page!');
});
// Listening to the port
let PORT = 3000;
app.listen(PORT)
// FINISH!
Example 4: expressjs server
// npm init
// npm i express
const express = require('express');
const server = express();
const PORT = 3000;
// Body parser
server.use(express.json());
// Homme page
server.get('/', (req, res) => {
return res.send("<h1 style='text-align: center;'>Hello,<br />from the Express.js server!</h1>");
})
// About page
server.get('/about', (req, res) => {
return res.send('<h2 style="text-align:center">About us</h2>');
})
// 404 page
server.use((req, res, next) =>{
res.status(404);
// respond with html page
if (req.accepts('html')) {
res.sendFile(__dirname + '/error404.html');
return;
}
// respond with json
else if (req.accepts('json')){
res.send({
status: 404,
error: 'Not found'
});
return;
}
// respond with text
else {
res.type('txt').send('Error 404 - Not found');
}
});
// Listening to the port
server.listen(PORT, () => {
console.log(`Server is running on port ${PORT}`);
});
// Running the server: node server.js
Example 5: simple express server
const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;
app.get('/', (req, res) => {
res.send('<h1>Some HTML</h1>');
res.send('<p>Even more HTML</p>');
});
app.listen(PORT, () => console.log(`Server is listening on port ${PORT}`));
Example 6: sample express app
const express = require('express')
const app = express()
const port = 3000
app.get('/', (req, res) => res.send('Hello World!'))
app.listen(port, () => console.log(`Example app listening at http://localhost:${port}`))