React

Question 1

Name some ways to optimize

Answer 1

• bundle your build
• utilizing memo/usememo/callback CORRECTLY for rerenders
• lazy loading
• • React.Suspense and React.Lazy (can you give example?)

Question 2

• can you tell me how to use React.Lazy?

Answer 2

• old way:

import LazyComponent from ‘./LazyComponent’;

• new way:

const LazyComponent = React.Lazy(() => import(‘./LazyComponent’));

function MyComponent() {
  return (
    Loading...}>

);
}

Question 3

what do class components have that functional components do not?

Answer 3

• error boundaries. using

static getDerivedStateFromError() to render a fallback UI after an error has been thrown

componentDidCatch() to log error information