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@supunlakmal/hooks

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A collection of reusable React hooks

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import { useState, useEffect, useCallback } from 'react'; /** * A hook that manages state with localStorage, automatically syncing between state and storage. * * @param key - The localStorage key to store the value under * @param initialValue - The initial value to use if no value is found in localStorage * @returns A tuple containing the current value and a function to update it */ export const useLocalStorage = (key, initialValue) => { // Create state to store our value // Pass initialState function to useState so logic is only executed once const [storedValue, setStoredValue] = useState(() => { if (typeof window === 'undefined') { return initialValue; } try { // Get from local storage by key const item = window.localStorage.getItem(key); // Parse stored json or if none return initialValue return item ? JSON.parse(item) : initialValue; } catch (error) { // If error also return initialValue console.error(`Error reading localStorage key "${key}":`, error); return initialValue; } }); // Return a wrapped version of useState's setter function that // persists the new value to localStorage. const setValue = useCallback((value) => { try { // Allow value to be a function so we have same API as useState const valueToStore = value instanceof Function ? value(storedValue) : value; // Save state setStoredValue(valueToStore); // Save to local storage if (typeof window !== 'undefined') { window.localStorage.setItem(key, JSON.stringify(valueToStore)); } } catch (error) { console.error(`Error setting localStorage key "${key}":`, error); } }, [key, storedValue]); // Listen for changes to this localStorage key in other tabs/windows useEffect(() => { function handleStorageChange(event) { if (event.key === key && event.newValue) { try { // When local storage changes, update the state setStoredValue(JSON.parse(event.newValue)); } catch (error) { console.error(`Error parsing localStorage change for key "${key}":`, error); } } } // Add event listener for 'storage' events if (typeof window !== 'undefined') { window.addEventListener('storage', handleStorageChange); return () => window.removeEventListener('storage', handleStorageChange); } return undefined; }, [key]); return [storedValue, setValue]; }; //# sourceMappingURL=useLocalStorage.js.map