Express.js express.urlencoded() Function

The express.urlencoded() function is a built-in middleware function in Express. It parses incoming requests with URL-encoded payloads and is based on a body parser.

Syntax:

express.urlencoded( [options] )

Parameter: The options parameter contains various properties like extended, inflate, limit, verify, etc.

Return Value: It returns an Object.

Installation of the express module:

You can visit the link to Install the 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 the 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

Project Structure:

Example 1: Filename: index.js

javascript

const express = require('express');
const app = express();
const PORT = 3000;

app.use(express.urlencoded({ extended: false }));

app.post('/', function (req, res) {
    console.log(req.body);
    res.end();
});

app.listen(PORT, function (err) {
    if (err) console.log(err);
    console.log("Server listening on PORT", PORT);
});

Steps to run the program:

Make sure you have installed the express module using the following command: 

npm install express

Run the index.js file using the below command: 

node index.js

Output:

Console Output:

Server listening on PORT 3000

Browser Output:

Now make a POST request to http://localhost:3000/ with header set to ‘content-type: application/x-www-form-urlencoded’ and body {“name”:”GeeksforGeeks”}, then you will see the following output on your console: 

Example 2: Filename: index.js

javascript

const express = require('express');
const app = express();
const PORT = 3000;

// Without this middleware
// app.use(express.urlencoded({extended:false}));

app.post('/', function (req, res) {
    console.log(req.body);
    res.end();
});

app.listen(PORT, function (err) {
    if (err) console.log(err);
    console.log("Server listening on PORT", PORT);
});

Steps to run the program:

Run the index.js file using the below command: 

node index.js

Now make a POST request to http://localhost:3000/ with header set to ‘content-type: application/x-www-form-urlencoded’ and body {“title”:”GeeksforGeeks”}, then you will see the following output on your console: 

Output:

Server listening on PORT 3000
undefined

Reference: https://expressjs.com/en/4x/api.html#express.urlencoded