Complete Guide to React Hooks

React Hooks revolutionized how we write React components by allowing us to use state and other React features in functional components.

What are React Hooks?

Hooks are functions that let you "hook into" React state and lifecycle features from function components. They were introduced in React 16.8.

Built-in Hooks

useState

The most commonly used hook for managing local component state.

import React, { useState } from 'react';

function Counter() {
  const [count, setCount] = useState(0);

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

useEffect

Lets you perform side effects in function components.

import React, { useState, useEffect } from 'react';

function Example() {
  const [count, setCount] = useState(0);

  useEffect(() => {
    document.title = `You clicked ${count} times`;
  });

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

Best Practices

1. Only call hooks at the top level
2. Only call hooks from React functions
3. Use ESLint plugin for hooks
4. Keep effects focused and small

Conclusion

React Hooks provide a more direct API to the React concepts you already know. They offer a powerful and expressive way to reuse stateful logic between components.