useLocalStorage Hook
Sync React state with localStorage — handles JSON serialization and SSR safely.
#react#hooks#typescript#storage
typescript
import { useEffect, useState } from 'react';
export function useLocalStorage<T>(key: string, initialValue: T) {
const [storedValue, setStoredValue] = useState<T>(() => {
if (typeof window === 'undefined') return initialValue;
try {
const item = window.localStorage.getItem(key);
return item ? (JSON.parse(item) as T) : initialValue;
} catch {
return initialValue;
}
});
const setValue = (value: T | ((val: T) => T)) => {
try {
const valueToStore =
value instanceof Function ? value(storedValue) : value;
setStoredValue(valueToStore);
if (typeof window !== 'undefined') {
window.localStorage.setItem(key, JSON.stringify(valueToStore));
}
} catch (error) {
console.error(error);
}
};
return [storedValue, setValue] as const;
}