Mastering the Basics of XMLHttpRequest: A Beginner’s Guide

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Navigating the world of web development can be daunting, especially when it comes to understanding the fundamentals of making HTTP requests. In this article, we’ll dive into the basics of the XMLHttpRequest object, a powerful tool for interacting with servers and fetching data.

What is XMLHttpRequest?

The XMLHttpRequest object is a JavaScript API that allows you to make HTTP requests to a server and receive responses. It’s a crucial component in the world of AJAX (Asynchronous JavaScript and XML), enabling you to update web pages without having to reload the entire page.

Making a Basic Request

Let’s start with a simple example of how to use the XMLHttpRequest object:

// Create a new XMLHttpRequest object
const xhr = new XMLHttpRequest();

// Open the request
xhr.open('GET', 'https://api.example.com/data');

// Send the request
xhr.send();

// Handle the response
xhr.onreadystatechange = function() {
  if (xhr.readyState === 4 && xhr.status === 200) {
    console.log(xhr.responseText);
  }
};

In this example, we:

1. Create a new XMLHttpRequest object.
2. Open the request with the open() method, specifying the HTTP method (GET) and the URL.