What are the best practices for using custom hooks in React?

What are the best practices for using custom hooks in React?

When using custom hooks in React, it's important to follow a few best practices: 1. Naming: Start with 'use' to indicate it's a hook. 2. Reusability: Ensure hooks are reusable across components. 3. Separation of Concerns: Keep hooks focused on a single responsibility. 4. Avoid Side Effects: Use hooks like useEffect for side effects instead of placing them in custom hooks.

Can you give an example of a custom hook?

Sure! Here's a simple example of a custom hook that manages a counter:

import { useState } from 'react';

function useCounter(initialValue = 0) {
    const [count, setCount] = useState(initialValue);
    const increment = () => setCount(c => c + 1);
    const decrement = () => setCount(c => c - 1);
    return { count, increment, decrement };
}

You can use this hook in your components to manage a counter state.

What should I avoid when creating custom hooks?

Avoid the following when creating custom hooks: 1. Mutating State Directly: Always use state setters. 2. Using Hooks Conditionally: Hooks should always be called at the top level of your component. 3. Overcomplicating Logic: Keep your hooks simple and focused.

How do I test custom hooks?

You can test custom hooks using libraries like React Testing Library or Enzyme. Create a test component that uses the hook and then assert the expected behavior. For example:

import { renderHook, act } from '@testing-library/react-hooks';
import useCounter from './useCounter';

test('should increment counter', () => {
    const { result } = renderHook(() => useCounter());
    act(() => {
        result.current.increment();
    });
    expect(result.current.count).toBe(1);
});