Altcademy - a Forbes magazine logo Best Coding Bootcamp 2023

How to send parameter in ajax call in ReactJS

Introduction

Welcome to another exciting journey into the world of programming, where we'll explore the concept of sending parameters in an Ajax call using ReactJS. Don't worry if the phrase "sending parameters in an Ajax call" seems daunting. We'll break it down in simpler terms before diving into the technicalities.

Breaking Down the Jargons

Before we start, let's clarify a few terms.

ReactJS: This is a popular JavaScript library used in building user interfaces, particularly for single-page applications. You can think of it as a tool to build the visual part of your web application, the part that users interact with.

Ajax (Asynchronous JavaScript and XML): This is a method used to update parts of a web page, without reloading the whole page. It works by sending data to, and retrieving data from, a server asynchronously (in the background). This makes the web page more interactive and faster.

Parameters: In programming, parameters are the specific data or values that a function uses to perform its task. Imagine you have a robot that paints walls. The color of the paint to use could be a parameter you give to the robot.

Having clarified these terms, let's explore how to send parameters in an Ajax call in ReactJS.

Getting Started with Ajax in ReactJS

The first step is to set up an Ajax call. This can be done using various methods, one of the simplest being the fetch() function provided by the browser.

Here's a basic example:

fetch('https://api.example.com/data', {
    method: 'GET', 
})
.then(response => response.json())
.then(data => console.log(data))
.catch((error) => {
  console.error('Error:', error);
});

The fetch() function takes in two parameters: the URL you're making the request to and an options object where you set the method type ('GET', 'POST', etc.). Once the request is made, the function returns a Promise which you can then manipulate using .then() or catch any errors with .catch().

Sending Parameters in a GET Request

When sending parameters in a GET request, these parameters are typically sent in the URL. This is often in the form of a query string - that part of the URL that comes after a ? character.

For example, let's say we want to get data about a specific user from our API. The user's ID could be the parameter we send. The fetch call might look like this:

const userId = 123;
fetch(`https://api.example.com/user?id=${userId}`, {
    method: 'GET', 
})
.then(response => response.json())
.then(data => console.log(data))
.catch((error) => {
  console.error('Error:', error);
});

Here, the user ID is appended to the URL as a query string. When the server receives this request, it will look for the user with the corresponding ID and return the data.

Sending Parameters in a POST Request

What if you need to send a lot of data, such as an entire user profile? This is where POST requests come in. Unlike GET requests, POST requests send parameters in the body of the request, not in the URL.

Here's an example:

const userProfile = {
    name: 'John Doe',
    email: 'john@example.com',
    password: 'secret'
};

fetch('https://api.example.com/user', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json',
    },
    body: JSON.stringify(userProfile),
})
.then(response => response.json())
.then(data => console.log(data))
.catch((error) => {
  console.error('Error:', error);
});

In this example, userProfile is the parameter we're sending. We specify the Content-Type as 'application/json' in the headers and then convert userProfile into a JSON string with JSON.stringify(userProfile) before sending it in the body.

Wrap Up

That's it! We've learned how to send parameters in an Ajax call in ReactJS. Just remember, for GET requests, parameters are sent in the URL, typically as a query string. For POST requests, parameters are sent in the body of the request.

ReactJS and Ajax are like the post office of the web. You can send a letter (the parameter) either in an envelope (POST request) or written on the outside of the postcard (GET request). The choice depends on how much data you're sending and how you want to send it.

Remember, practice is key in programming. Try making some GET and POST requests on your own and see how it works. Happy coding!