What are some performance tips for using useEffect in React?

What are some performance tips for using useEffect in React?

To optimize useEffect, consider the following tips: 1. Specify dependencies accurately to avoid unnecessary re-renders. 2. Use cleanup functions to prevent memory leaks. 3. Avoid using useEffect for synchronous operations; prefer it for side effects.

Can you explain how dependencies work in useEffect?

Sure! The dependency array in useEffect determines when the effect runs. If you include variables in this array, the effect will re-run whenever those variables change. If the array is empty, the effect runs only once after the initial render.

What happens if I don't include a dependency?

If you omit a dependency, the effect will run after every render, which can lead to performance issues and infinite loops if the effect modifies state that triggers a re-render.

Are there any common mistakes to avoid with useEffect?

Yes, common mistakes include not specifying dependencies correctly, using state updates inside the effect without cleanup, and performing heavy computations directly in the effect.