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React useEffect not triggering on dependency change due to shallow comparison

👀 Views: 2 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-08
react useEffect state-management JavaScript

I'm confused about I'm learning this framework and I've looked through the documentation and I'm still confused about I'm working with an scenario where my `useEffect` hook in a React component isn't triggering when the dependency changes... I've double-checked that the dependency array includes the variable I want to watch, but it seems like React is using a shallow comparison, and it's not recognizing the change. Here's a simplified version of my code: ```javascript import React, { useEffect, useState } from 'react'; const MyComponent = () => { const [data, setData] = useState({ id: 1, name: 'Item 1' }); useEffect(() => { console.log('Data changed:', data); }, [data]); const updateData = () => { // This creates a new object, but with the same values setData({ id: 1, name: 'Item 1' }); }; return <button onClick={updateData}>Update Data</button>; }; export default MyComponent; ``` When I click the button, I expect the `useEffect` to log 'Data changed: { id: 1, name: 'Item 1' }', but it doesn't seem to fire at all. I thought that creating a new object would trigger the re-render and consequently the `useEffect`, but it appears that React is treating the object as the same because the values are identical. I've tried using a `useRef` to hold the previous state and comparing it manually, but that feels a bit hacky. Is there a cleaner way to handle this scenario, or should I be using a different approach to force `useEffect` to recognize changes in the object? Any insights or workarounds would be appreciated! Also, I'm using React version 17.0.2. How would you solve this? This is for a service running on macOS. Thanks for taking the time to read this! I'm open to any suggestions.