ReactHooksJavaScript
React Hooks: A Complete Deep Dive
Understanding React hooks from basics to advanced patterns with practical examples.
7 min read
React Hooks: A Complete Deep Dive
Hooks revolutionized React development. Let's explore them from basics to advanced patterns.
Essential Hooks
useState
const [count, setCount] = useState(0);
// Functional update
setCount(prev => prev + 1);
useEffect
useEffect(() => {
const subscription = subscribe();
return () => subscription.unsubscribe();
}, [dependency]);
useCallback & useMemo
const memoizedCallback = useCallback(() => {
doSomething(a, b);
}, [a, b]);
const memoizedValue = useMemo(() => computeExpensive(a), [a]);
Custom Hooks
function useLocalStorage<T>(key: string, initial: T) {
const [value, setValue] = useState<T>(() => {
const stored = localStorage.getItem(key);
return stored ? JSON.parse(stored) : initial;
});
useEffect(() => {
localStorage.setItem(key, JSON.stringify(value));
}, [key, value]);
return [value, setValue] as const;
}
Best Practices
- Keep hooks at the top level - Never inside conditions
- Use the dependency array correctly - Include all dependencies
- Extract logic into custom hooks - Reuse and test
Hooks make functional components powerful and composable!