Building Reusable Components with React

1. Introduction

React is a powerful library for building user interfaces. One of its key features is the ability to create reusable components. This lesson will guide you through the process of building reusable components in React, highlighting important concepts, best practices, and providing practical examples.

2. Key Concepts

2.1 What is a Component?

A component in React is a self-contained piece of UI that can be reused throughout your application. Components can be functional or class-based:

Functional Components: Simple functions that return JSX.
Class Components: ES6 classes that can manage their own state and lifecycle methods.

2.2 Props and State

Components can receive data through props and maintain internal data using state.

Props: Read-only data passed from parent to child components.

State: Mutable data managed within a component itself.

3. Step-by-Step Process

Note: Ensure you have Node.js and npm installed to create a React app.

Set up your React environment using Create React App:

npx create-react-app my-app

Navigate into your project directory:

cd my-app

Create a new component, e.g., Button.js:


import React from 'react';

const Button = ({ label, onClick }) => {
    return (
        
    );
};

export default Button;

Use the component in your App.js:


import React from 'react';
import Button from './Button';

const App = () => {
    const handleClick = () => alert('Button clicked!');

    return (
        
            Hello, World!
            
    );
};

export default App;

4. Best Practices

Keep components small and focused on a single task.
Use prop types to enforce the type of props a component should receive.
Use default props to define default values for props.
Utilize hooks for managing state in functional components.
Document your components with comments for better maintainability.

5. FAQ

What are reusable components?

Reusable components are those that can be used multiple times across different parts of an application without needing to rewrite code.

How do I pass data to a component?

You pass data to a component using props, which can be accessed within the component as an object.

Can I use state in functional components?

Yes, you can use state in functional components by utilizing the useState hook.