How does React’s shouldComponentUpdate method work?

Short answer: shouldComponentUpdate is a lifecycle method in class components that determines whether a component should re-render.

Explain a bit more

By default, a component re-renders when state or props change, but shouldComponentUpdate allows you to optimize this behavior. Return false to prevent a re-render. Return true (or omit the method) to allow a re-render. Example: class MyComponent extends React.Component { shouldComponentUpdate(nextProps, nextState) { // Prevent re-render if props haven't changed return nextProps.name !== this.props.name;

Example code

} render() { return <div>{this.props.name}</div>;
}
}

Real-world example (ShopNest)

ShopNest’s storefront is React: components for ProductCard, CartDrawer, and CheckoutForm, with hooks for local UI state.

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.