React Overview
Table of Contents
Introduction
React is a JavaScript library for building user interfaces. It makes it painless to create interactive UIs. React was created by Facebook and is maintained by Facebook and a community of individual developers and companies.
Core Concepts
Components
Components are the building blocks of a React application. A component is a self-contained module that renders some output. Components can be functional or class-based.
JSX
JSX (JavaScript XML) is a syntax extension for JavaScript that looks similar to XML or HTML. It is used with React to describe what the UI should look like.
State and Props
- State: A component’s state is an object that determines how that component renders and behaves.
- Props: Props (short for properties) are read-only attributes passed from parent to child components.
Lifecycle Methods
Lifecycle methods are special methods in class components that run at different stages of a component’s lifecycle (mounting, updating, and unmounting).
Advanced Topics
Hooks
Hooks are functions that let you use state and other React features in functional components. Common hooks include useState, useEffect, and useContext.
Context API
The Context API allows for global state management. It provides a way to pass data through the component tree without having to pass props down manually at every level.
Routing
React Router is a library used to handle routing in React applications, enabling navigation among different views or pages.
Best Practices
- Use functional components and hooks for new code.
- Keep components small and focused.
- Lift state up to the closest common ancestor when multiple components need to share it.
- Use prop types or TypeScript to enforce component interfaces.
- Optimize performance using React.memo and useCallback.