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How to write data in json file using ReactJS

Getting Started with JSON in ReactJS

JSON or JavaScript Object Notation is a popular data format with a diverse range of applications in data interchange and storage. Today, we'll be focusing on how to write data in a JSON file using ReactJS, a JavaScript library for building user interfaces. ReactJS simplifies the process of updating and rendering of the right components when your data changes.

What is JSON?

JSON is a lightweight format for storing and transporting data, often used when data is sent from a server to a web page. In layman's terms, it's like a waiter taking your order (data) from the table (client) to the kitchen (server) and bringing the meal (data) back to serve.

Why Use JSON?

JSON is easy to understand, write, and read. It is language-independent, which means it can work with virtually any programming language, not just JavaScript.

JSON and ReactJS: The Perfect Duo

ReactJS is a library used for building user interfaces, primarily for single-page applications. It handles the view layer for web and mobile apps. React allows you to design simple views for each state in your application, and it will efficiently update and render the right components when your data changes.

Think of ReactJS as a very efficient artist who paints (renders) a picture (view) for you. When you want to change something in the picture (data changes), the artist doesn't start over but simply adjusts what's necessary (updates the right components).

Writing Data to a JSON file in ReactJS

Let's imagine we're building a simple web page to store our favorite books. We want to store the book title, author, and a boolean to know if we've read it or not.

The first thing we need to do is to create our JSON file. We'll call it books.json. It will look something like this:

    "id": 1,
    "title": "To Kill a Mockingbird",
    "author": "Harper Lee",
    "read": false

To write to this file using ReactJS, we'll use the fs (File System) module provided by Node.js. The fs module provides an API for interacting with the file system in a manner closely modeled around standard POSIX functions.

First, we need to import the fs module:

const fs = require('fs');

Next, we define our new book data:

let book = {
  title: "1984",
  author: "George Orwell",
  read: true

Now, we read our JSON file and convert it into a JSON object:

let data = fs.readFileSync('books.json');
let books = JSON.parse(data);

Then, we push our new book into the books array:


Finally, we write our new data back to the JSON file:

fs.writeFile('books.json', JSON.stringify(books), function(err) {
  if (err) {

And there you have it! You've successfully written data to a JSON file using ReactJS.


Writing data to a JSON file using ReactJS might seem like a daunting task at first, but once you break it into smaller parts, it's a piece of cake - or better yet, a slice of JSON pie!

In this tutorial, we've seen how to write to a JSON file using ReactJS, but the possibilities are endless. You can add more complex data, handle errors more gracefully, or even add a user interface to add books! Remember, practice makes perfect. So, keep exploring, keep learning, and keep coding.