req params express code example

Example 1: express js params

app.get('/path/:name', function(req, res) { // url: /path/test
  console.log(req.params.name);  // result: test
});

// OR

app.get('/path', function(req, res) {  // url: /path?name='test'
  console.log(req.query['name']);  // result: test
});

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: express redirect

res.redirect('/foo/bar')
res.redirect('http://example.com')
res.redirect(301, 'http://example.com')
res.redirect('../login')

Example 4: expressjs query params

// GET /search?q=tobi+ferret
console.dir(req.query.q)
// => 'tobi ferret'

// GET /shoes?order=desc&shoe[color]=blue&shoe[type]=converse
console.dir(req.query.order)
// => 'desc'

console.dir(req.query.shoe.color)
// => 'blue'

console.dir(req.query.shoe.type)
// => 'converse'

// GET /shoes?color[]=blue&color[]=black&color[]=red
console.dir(req.query.color)
// => ['blue', 'black', 'red']

Example 5: express url redirect

const app = require('express')();

// The `res.redirect()` function sends back an HTTP 302 by default.
// When an HTTP client receives a response with status 302, it will send
// an HTTP request to the URL in the response, in this case `/to`
app.get('/from', (req, res) => {
  res.redirect('/to');
});
app.get('/to', (req, res) => res.send('Hello, World!'));

Example 6: express render

// send the rendered view to the client
res.render('index')

// if a callback is specified, the rendered HTML string has to be sent explicitly
res.render('index', function (err, html) {
  res.send(html)
})

// pass a local variable to the view
res.render('user', { name: 'Tobi' }, function (err, html) {
  // ...
})