👀 Views: 3 💬 Answers: 1 📅 Created: 2025-06-04

reactjs useEffect state-management JavaScript

I've been researching this but I'm encountering an issue where `useEffect` seems to be capturing an outdated state when I use `setTimeout` within an async function. The goal is to fetch some data after a delay when a user clicks a button, but I see stale data being logged instead of the latest state. Here's a simplified version of my component: ```javascript import React, { useState, useEffect } from 'react'; const MyComponent = () => { const [count, setCount] = useState(0); const [data, setData] = useState(null); const fetchData = async () => { // Simulate an API call return new Promise(resolve => setTimeout(() => resolve(`Data for count: ${count}`), 1000)); }; useEffect(() => { const handleFetch = async () => { const result = await fetchData(); setData(result); }; const timerId = setTimeout(handleFetch, 2000); return () => clearTimeout(timerId); }, [count]); return ( <div> <p>Count: {count}</p> <p>Data: {data}</p> <button onClick={() => setCount(c => c + 1)}>Increment</button> </div> ); }; export default MyComponent; ``` When I click the 'Increment' button multiple times quickly, I notice that the `data` displayed does not reflect the latest `count` value. Instead, it shows data corresponding to the value of `count` from two clicks ago, even though I expected it to reflect the most recent increment. Additionally, I'm getting a warning about React detecting multiple updates due to the async nature of the state updates. I’ve tried various approaches to resolve this by using refs to hold the latest `count`, but that adds more complexity. Is there a more straightforward way to ensure I capture the latest state in such scenarios? For reference, this is a production desktop app.