Custom hooks encapsulate reusable stateful logic. Extract common patterns like data fetching, form handling, and subscriptions into hooks. Components become simpler, focusing on rendering while hooks manage behavior.
Hook Design Principles
Name hooks with use prefix following React convention. Return values matching component needs—data, handlers, state. Handle cleanup in useEffect return functions. Accept configuration as parameters for flexibility.
- Extract repeated useEffect patterns into custom hooks
- Return objects for multiple values enabling destructuring
- Implement cleanup preventing memory leaks on unmount
- Use TypeScript generics for type-safe reusable hooks
- Test hooks with renderHook from testing-library
Common Hook Patterns
useAsync manages async operation state. useLocalStorage syncs state with storage. useDebounce delays value updates. usePrevious tracks previous render values. These patterns solve common problems elegantly.