Express.js res.end() Function

The res.end() function is used to end the response process. This method actually comes from the Node core, specifically the response.end() method of HTTP.ServerResponse. Use to quickly end the response without any data.

Syntax:

res.end([data] [, encoding])

Parameters: The default encoding is ‘utf8’ and the data parameter is basically the data with which the user wants to end the response.

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;

// Without middleware
app.get('/', function (req, res) {
    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 open your browser and go to http://localhost:3000/ and you will see the blank response as this function is used to quickly end the response without any data. 

Example 2: Filename: index.js

javascript

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

// With middleware
app.use('/user', function (req, res, next) {
    console.log("/user called")
    res.end();
})

app.get('/user', function (req, res) {
    console.log("User Page")
    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

Output:

Now open your browser and go to http://localhost:3000/user, then you will see the following output on your console: 

Server listening on PORT 3000
/user called

Reference: https://expressjs.com/en/4x/api.html#res.end