React Advanced Topics 3

Question 1

What is the React Context API primarily used for?

Accepted Answer

Sharing data across the component tree without prop drilling

Answer

Context lets you pass data through the tree without manually passing props at every level.

Question 2

What does a custom hook allow you to do?

Accepted Answer

Extract and reuse stateful logic across components

Answer

Custom hooks package reusable stateful logic into a function whose name starts with 'use'.

Question 3

What is the purpose of React.lazy?

Accepted Answer

To enable code-splitting by dynamically importing a component

Answer

React.lazy lets you render a dynamically imported component for code-splitting.

Question 4

Which component must wrap a React.lazy component to handle its loading state?

Accepted Answer

Suspense

Answer

Suspense displays fallback UI while a lazy component is loading.

Question 5

What does the useReducer hook help manage?

Accepted Answer

Complex state logic with multiple sub-values or transitions

Answer

useReducer is suited to complex state managed through dispatched actions and a reducer function.

React Practice Test