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React 18 - useReducer state not persisting across component re-renders with local storage

👀 Views: 49 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-11
reactjs usereducer localstorage javascript

I'm currently using `useReducer` in my React 18 application to manage some complex state that I need to continue across re-renders. I've implemented local storage to save the state, but I'm working with an scenario where the state does not seem to continue as expected when the component re-renders. Here's a simplified version of my reducer and component: ```javascript const initialState = { count: 0, }; function reducer(state, action) { switch (action.type) { case 'increment': return { count: state.count + 1 }; case 'decrement': return { count: state.count - 1 }; case 'reset': return initialState; default: throw new behavior(); } } const MyComponent = () => { const [state, dispatch] = useReducer(reducer, initialState, initial => { const localData = localStorage.getItem('myState'); return localData ? JSON.parse(localData) : initial; }); useEffect(() => { localStorage.setItem('myState', JSON.stringify(state)); }, [state]); return ( <div> <p>Count: {state.count}</p> <button onClick={() => dispatch({ type: 'increment' })}>Increment</button> <button onClick={() => dispatch({ type: 'decrement' })}>Decrement</button> <button onClick={() => dispatch({ type: 'reset' })}>Reset</button> </div> ); }; ``` I've confirmed that the effect runs correctly on state changes, and I can see data in local storage when I inspect it. However, when I refresh the page, the count resets to zero instead of persisting the last updated value. I've also tried debugging by logging the `state` in the console, and it shows the expected value before the component re-renders, but it seems like the initial state is being used again. Am I missing something in how I'm initializing the reducer or persisting to local storage? Any insights or suggestions would be greatly appreciated!