How do hooks affect component lifecycle?

Short answer: In class components, the lifecycle is managed using methods like componentDidMount, componentDidUpdate, and componentWillUnmount.

Explain a bit more

With hooks, these are replaced with useEffect, which can mimic any lifecycle behavior. Lifecycle Mapping: componentDidMount: Use useEffect with an empty dependency array ([]). componentDidUpdate: Use useEffect with dependencies. componentWillUnmount: Return a cleanup function inside useEffect.

Example code

useEffect(() => { // Equivalent to componentDidMount and componentDidUpdate console.log("Component mounted or updated"); return () => { // Equivalent to componentWillUnmount console.log("Cleanup before component unmount"); }; }, [dependencies]); // Will run on mount and update based on dependencies

Real-world example (ShopNest)

ShopNest’s cart icon uses useState for count and useEffect to load the cart once on mount.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.