What is JSX in ReactJS

React was developed by Facebook to solve their own issues with large applications and since its release in 2013, it has exploded in popularity. But, what about this “JSX” that you often hear associated with React?

What exactly is JSX?

JSX, short for JavaScript XML, is a syntax extension for JavaScript. It was written to be used with React to describe what the user interface should look like.

JSX produces React “elements” which, as the building blocks of React apps, enable developers to construct the application’s UI.

In simple terms, it’s a combination of JavaScript and HTML. If you’ve ever seen code that looks like HTML embedded directly within JavaScript, then you’ve probably seen JSX.

With JSX, we can write HTML structures in the same file that contains JavaScript code. This makes code writing, especially for components, much easier and cleaner. Also, it saves us from many confusing JavaScript workarounds when it comes to manipulating the DOM.

// JSX Example

const element = <h1>Hello, world!</h1>;

One of the main advantages of using JSX is that it allows you to see the layout within the code, making it more comfortable to understand and maintain.

It eliminates the need to create complex UIs using JavaScript alone, which can be rather cumbersome. Additionally, JSX prevents injection attacks. It means it’s safe to embed user input in JSX because React DOM escapes any values embedded in JSX before rendering them.

But there’s a bit of a catch with JSX: browsers can’t read it directly. Browsers can only read JavaScript objects, but JSX isn’t a regular JavaScript object. Hence, JSX must be transformed into regular JavaScript before running in your browser. We use tools like Babel or Webpack, JavaScript compilers that can take your JSX code and turn it into regular JavaScript that the browser can understand.

Contrary to popular belief, it is not necessary to use JSX to use React. But it’s these advantages that make JSX popular among React developers. It reduces complexity, brings syntax closer to the familiar realm of HTML, and offers a cleaner and more logical code organization.

To conclude, JSX is not a programming language but rather a tool that helps you write and add HTML to your JavaScript code. It’s a powerful and essential part of ReactJS, and understanding it will lead to more efficient, cleaner, and easier-to-understand code. So, if you are stepping into the world of React, arm yourself with a good understanding of JSX. It might seem a little intimidating at first, but once you get used to it, you’ll find it a convenient and useful tool in your React toolkit.

Check out more tutorials here.

What exactly is JSX?

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