Skip to content
Related Articles

Related Articles

Express.js express.Router() Function

Improve Article
Save Article
  • Difficulty Level : Basic
  • Last Updated : 16 Jun, 2022
Improve Article
Save Article

The express.Router() function is used to create a new router object. This function is used when you want to create a new router object in your program to handle requests. 

Syntax:

express.Router( [options] )

Optional Parameters:

  • case-sensitive: This enables case sensitivity.
  • mergeParams: It preserves the req.params values from the parent router.
  • strict: This enables strict routing.

Return Value: This function returns the New Router Object. Installation of express module:

npm install express
  • After installing the express module, you can check your express version in command prompt using the command.
npm version express
  • After that, you can just create a folder and add a file for example, index.js. To run this file you need to run the following command.
node index.js

Example 1: Filename: index.js 

javascript




var express = require('express');
var app = express();
var PORT = 3000;
 
// Single routing
var router = express.Router();
   
router.get('/', function (req, res, next) {
    console.log("Router Working");
    res.end();
})
 
app.use(router);
 
app.listen(PORT, function(err){
    if (err) console.log(err);
    console.log("Server listening on PORT", PORT);
});


Steps to run the program:

  • The project structure will look like this:
  • Make sure you have installed express module using the following command:
npm install express
  • Run index.js file using below command:
node index.js

Output:

Server listening on PORT 3000
  • Now open your browser and go to http://localhost:3000/, you will see the following output on your screen:
Server listening on PORT 3000
Router Working

Example 2: Filename: index.js 

javascript




var express = require('express');
var app = express();
var PORT = 3000;
 
// Multiple routing
var router1 = express.Router();
var router2 = express.Router();
var router3 = express.Router();
    
router1.get('/user', function (req, res, next) {
    console.log("User Router Working");
    res.end();
});
  
router2.get('/admin', function (req, res, next) {
    console.log("Admin Router Working");
    res.end();
});
 
router2.get('/student', function (req, res, next) {
    console.log("Student Router Working");
    res.end();
});
 
app.use(router1);
app.use(router2);
app.use(router3);
  
app.listen(PORT, function(err){
    if (err) console.log(err);
    console.log("Server listening on PORT", PORT);
});


Run index.js file using below command:

node index.js

Now make a GET request to http://localhost:3000/user, http://localhost:3000/admin and http://localhost:3000/student, then you will see the following output on your console:

Server listening on PORT 3000
User Router Working
Admin Router Working
Student Router Working

Reference: Official Documentation


My Personal Notes arrow_drop_up
Related Articles

Start Your Coding Journey Now!