React Concepts

What is the purpose of useState in React?

• useState is used to define props in React.

• useState is used to style components in React.

• useState is used to fetch data from APIs in React.

• useState is used to add state variables to functional components in React.

Explain the role of useEffect hook in React.

• The useEffect hook is responsible for managing state in React components.

• The useEffect hook is used for styling components in React.

• useEffect is primarily used for handling form submissions in React applications.

• The useEffect hook in React is used to perform side effects in function components.

Differentiate between class component and functional component in React.

• Functional components have access to lifecycle methods, unlike class components.

• Class components are simpler and more lightweight compared to functional components.

• Class components are ES6 classes with lifecycle methods, while functional components are simple functions that take props as arguments.

• Functional components are written in ES5 syntax, while class components use ES6 syntax.

How does useContext hook work in React?

• useContext hook works by accepting a context object (created using React.createContext) as an argument and returning the current context value for that context.

• useContext hook works by directly modifying the global state of the application

• useContext hook requires passing props down through multiple levels of components

• useContext hook can only be used with class components

When would you use a class component over a functional component in React?

• When you need to manage state, use lifecycle methods, or optimize performance.

• When you prefer less efficient components

• When you want to make your code more complex

• When you need to confuse other developers

What are the advantages of using functional components in React?

• Functional components are harder to test than class components

• Functional components are slower than class components

• Advantages of using functional components in React include better performance, easier testing, improved code readability, and enhanced reusability.

• Functional components have poor code readability compared to class components

How can you manage state in a functional component?

• Use global variables to store state

• Use the 'useState' hook in a functional component to manage state.

• Use the 'useEffect' hook to manage state

• Use class components instead of functional components

Discuss the lifecycle methods available in class components.

• componentWillMount

• componentDidUnmount

• Lifecycle methods available in class components include componentDidMount, componentDidUpdate, componentWillUnmount, shouldComponentUpdate, etc.

• componentShouldUpdate

What are the limitations of class components in React?

• Inefficient rendering, poor scalability

• Complex syntax, potential performance issues, difficulty in code reuse

• Limited functionality, lack of flexibility

• Inadequate state management, subpar component lifecycle

Explain the concept of props in React.

• Props in React are used for styling components.

• Props in React are used for handling state management.

• Props in React are read-only properties passed from parent to child components for customization and configuration.

• Props in React can only be passed from child to parent components.