express response json code example

Example 1: node js return json

var http = require('http');

var app = http.createServer(function(req,res){
    res.setHeader('Content-Type', 'application/json');
    res.end(JSON.stringify({ a: 1 }));
});
app.listen(3000);

// > {"a":1}

Example 2: express req get json

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

app.use(express.json());

app.post('*', (req, res) => {
  req.body;	// The json object sent to the server
});
const port = 3000;
app.listen(port, () => console.log(`Listening on port ${port}.`));

Example 3: http header express

app.get('/', (req, res) => {
  req.header('User-Agent')
})
// Use the Request.header() method to access
//one individual request header’s value

Example 4: 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) {
  // ...
})