Express.js router.METHOD() Function
The router.METHOD() method provides the routing functionality in Express, where METHOD is one of the HTTP methods, such as GET, PUT, POST, and so on, in lowercase.
Syntax:
router.METHOD(path, [callback, ...] callback)
Parameter: The path parameter specifies the path on the URL and callback is the function which is executed when this path is called.
Return Value: Since, it provides the routing functionality, so it can return responses.
Installation of express module:
- You can visit the link to Install express module. You can install this package by using this command.
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
var express = require( 'express' ); var app = express(); var router = express.Router(); var PORT = 3000; // Single route router.get( '/user' , function (req, res, next) { console.log( "GET request called" ); 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 make GET request to http://localhost:3000/, you can see the following output on your screen:
Server listening on PORT 3000 GET request called
Example 2: Filename: index.js
var express = require( 'express' ); var app = express(); var router = express.Router(); var PORT = 3000; // Multiple routes router.get( '/user' , function (req, res, next) { console.log( "GET request called" ); res.end(); }); router.post( '/user' , function (req, res, next) { console.log( "POST request called" ); res.end(); }); router. delete ( '/user' , function (req, res, next) { console.log( "DELETE request called" ); res.end(); }) app.use(router); 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 GET, POST, DELETE request to http://localhost:3000/, you can see the following output on your screen:
Server listening on PORT 3000 GET request called POST request called DELETE request called
Reference: https://expressjs.com/en/4x/api.html#router.METHOD