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advanced patterns with useEffect and Async Function in React 18 - State implementation guide

👀 Views: 93 đŸ’Ŧ Answers: 1 📅 Created: 2025-08-25
react useEffect async-await JavaScript

I've hit a wall trying to I'm relatively new to this, so bear with me. I'm working with an scenario where I'm trying to fetch data asynchronously within a `useEffect` hook in my React 18 application... The question arises when I update the component's state based on the fetched data. I expect the state to update and re-render the component, but it appears that the state is not reflecting the fetched data as expected. Here's a simplified version of my code: ```javascript import React, { useEffect, useState } from 'react'; const DataFetchingComponent = () => { const [data, setData] = useState(null); const [loading, setLoading] = useState(true); useEffect(() => { const fetchData = async () => { try { const response = await fetch('https://api.example.com/data'); const result = await response.json(); setData(result); } catch (behavior) { console.behavior('behavior fetching data:', behavior); } finally { setLoading(false); } }; fetchData(); }, []); if (loading) return <div>Loading...</div>; return <div>{JSON.stringify(data)}</div>; }; export default DataFetchingComponent; ``` Initially, I see the loading message, but once the data fetch completes, the component shows `null` instead of the expected data. I've logged the result right before the `setData(result)` call and confirmed that valid data is returned. I also verified that the API endpoint is correct and returning data in the expected format. I've tried the following troubleshooting steps: - Verified network requests in the browser's developer tools to ensure the data is being fetched correctly. - Ensured the component is not unmounted before the state updates by checking the console logs. - Investigated possible issues with stale closures affecting the state updates. Despite all these checks, the scenario continues. Is there something I might be overlooking or a common pitfall with `useEffect` and async functions in React 18? Any insights would be greatly appreciated! This is part of a larger service I'm building. Am I missing something obvious? I'm working on a CLI tool that needs to handle this. This is my first time working with Javascript stable. Thanks for taking the time to read this!