What is useEffect in React?

Can you explain what useEffect does in React?

Sure! useEffect is a hook that lets you perform side effects in function components. It runs after the render and can be used for data fetching, subscriptions, or manually changing the DOM.

How does useEffect differ from componentDidMount?

useEffect can run after every render, while componentDidMount only runs once after the initial render. You can control when useEffect runs by passing a dependency array.

What happens if I don't provide a dependency array?

If you don't provide a dependency array, useEffect will run after every render, which can lead to performance issues if not managed properly.

Can you give me an example of useEffect in action?

Absolutely! Here's a simple example:

useEffect(() => {
  fetchData(); // Fetch data when the component mounts
}, []);