Difference Between JS and JSX Files in React

React is a powerful JavaScript library developed by Facebook for creating user interfaces specifically for single-page applications. The component-based architecture allows developers to create reusable UI components. This makes the development process efficient and maintainable. A typical React application is structured in directories and files.

There are different file extensions used in React development, each with a particular purpose. For instance .js or .jsx files are for JavaScript and JSX code, respectively. On the other hand, .css files are for formatting elements. Knowing these file extensions is crucial for several reasons: improves code readability; helps fix bugs and ensures that developers can leverage the full potential of tools and libraries applied in their projects.

The .js File in React

The . js extension signifies that the file contains JavaScript code. These files are used to run JavaScript on a webpage or a server (in the case of Node. js) and can be referenced in HTML.

• Component Definition: Most React components are written as .js files, where each component can have its logic, markup, and styling.
• Utility Functions: Helper functions, constants, and configuration settings are often organized into separate .js files to maintain code clarity and reusability.
• State Management: Logic files for state management (such as using React's Context API or custom hooks) are also defined in .js files.
• Event Handling: Functions that handle user interactions (such as clicks or form submissions) are often defined in these files.

Example

In this example, we will create the basic React component in a .js file.

// Tutorial.js
import React from 'react';
const Tutorial = () => {
    return (
        <div>
            Hello, World!
        </div>
    );
};
export default Tutorial;

Output

In this example, the HelloWorld component is a functional component that returns a simple JSX structure. This is defined in a file named Tutorial.js and exported for use in other parts of the application.

Hello, World!

The .jsx File in React

JSX or JavaScript XML is a JavaScript syntax extension that allows developers to write HTML-like code directly within JavaScript. Files with the .jsx extension typically contain components written in JSX syntax, which React converts into calls. JavaScript Function This extension specifies that a file contains primarily JSX code, which makes it easier for developers and search engines.

• Readability: HTML-like syntax makes code more intuitive and readable.
• Improved developer experience: JSX supports features such as syntax highlighting and code linting, which improves the overall development experience.

Example

In this example we will create a component Using JSX Syntax.

// Greeting.jsx
import React from 'react';
const Greeting = ({ name }) => {
    return (
        <div>
            <h1>Hello, {name}!</h1>
            <p>Welcome to the world of React!</p>
        </div>
    );
};
export default Greeting;

Output

In this example, a Greeting component is defined in a file called Greeting. jsx. This component accepts a name prop and renders a personalized greeting using JSX syntax. Curly braces {} allow for embedding JavaScript expressions within the markup, showing how JSX can be used to create dynamic and interactive UIs

Difference Between a .js and .jsx File in React

Recommendations for using .js vs. .jsx

• Use .jsx for components with JSX syntax: If a file contains React components that employ JSX syntax, it's usually best to use the.jsx extension. It would inform other developers that it uses JSX code and adds reading.
• Use.js for purely JavaScript files: Files with nothing but JavaScript logic in them, such as utility functions, constants, or config settings. Use the extension.js. The point of this distinction is that it helps keep things more organized in the codebase. It separates files between components and utility/help files.

Understanding the difference between .js and .jsx files is important for working with React. .js files are typically used for general JavaScript code, like logic and utility functions, while .jsx files are better suited for writing React components using JSX syntax. Keeping this distinction helps make the code more readable and keeps the project well-organized.