What are Custom Hooks?
Custom hooks are JavaScript functions that use React’s built-in hooks to encapsulate and reuse stateful logic across multiple components. They follow the convention of starting with “use” and can call other hooks.Benefits of Custom Hooks
Reusability
Extract common logic into reusable functions that can be shared across components
Separation of Concerns
Keep component logic separate from presentation code for better maintainability
Testability
Test complex logic independently from component rendering
Composition
Combine multiple hooks to create more powerful abstractions
Available Custom Hooks
This project includes three custom hooks that demonstrate different patterns and use cases:useCounter
A simple hook for managing counter state with increment, decrement, and reset functionality.useCounter
Manage counter state with built-in increment, decrement, and reset operations
- Simple counting functionality
- Stepper components
- Quantity selectors
- Demo of basic custom hook patterns
useGifs
A sophisticated hook for searching and caching GIF results from the Giphy API.useGifs
Search GIFs with built-in caching and search history tracking
- API data fetching and state management
- Implementing client-side caching with useRef
- Managing search history
- Async operations in custom hooks
useWeather
A comprehensive hook for fetching weather data with geolocation, localStorage persistence, and auto-loading.useWeather
Fetch weather data with automatic caching and state management
- Complex async workflows with multiple API calls
- Local storage integration
- Auto-loading data on component mount
- Advanced error handling patterns
Custom Hook Best Practices
Always start with 'use'
Always start with 'use'
Custom hooks must follow the naming convention
useSomething to indicate they follow the Rules of Hooks.Follow the Rules of Hooks
Follow the Rules of Hooks
- Only call hooks at the top level (not inside loops, conditions, or nested functions)
- Only call hooks from React functions (components or custom hooks)
Return values consistently
Return values consistently
Return an object with named properties for better clarity, or an array for destructuring flexibility like useState.
Handle side effects properly
Handle side effects properly
Use
useEffect for side effects and useCallback for memoized functions to prevent unnecessary re-renders.Consider using TypeScript
Consider using TypeScript
Add type definitions to your custom hooks for better developer experience and catch errors early.