QUIZ ON : react - MISCELLANEOUS

MISCELLANEOUS

00:00:00

Question No# : 01 out of 50

What is the purpose of the "React.Children" API in React?

A. It provides utilities for working with React children components

B. It manages the lifecycle of React components

C. It handles form validation in React applications

D. It optimizes the rendering performance of React components

Question No# : 02 out of 50

Choose the component which should be overridden to stop the component from updating?

A. componentsDidUpdate

B. componentDidMaunt

C. willComponentsUpdate

D. ShouldComponentUpdate

Question No# : 03 out of 50

What is the recommended way to fetch data from an API in React?

A. Using the fetch API provided by the browser

B. Using third-party libraries like Axios or Fetch

C. Using the built-in "fetch" method provided by React

D. All of the above

Question No# : 04 out of 50

What is the purpose of React Router?

A. To handle server-side routing in React applications

B. To manage state and data flow in React components

C. To enable client-side routing in React applications

D. To provide a built-in testing framework for React applications

Question No# : 05 out of 50

Choose the correct statement in the context of uncontrolled components in ReactJS?

A. source of truth can be anything

B. source of truth is a component state

C. source of truth is DOM

D. none of the above

Question No# : 06 out of 50

What is the purpose of the "React.memo" higher-order component (HOC)?

A. It is used to memoize function components for performance optimization

B. It is used to create reusable custom hooks in React

C. It is used to manage state in class components

D. It is used to handle asynchronous operations and data fetching

Question No# : 07 out of 50

What is the concept of "lifting state up" in React?

A. Moving the state from a child component to its parent component

B. Moving the state from a parent component to its child component

C. Extracting the state into a separate utility function

D. Sharing the state between multiple unrelated components

Question No# : 08 out of 50

Which of the following is a must API for every React.js component?

A. render Component

B. Setinitial Component

C. render

D. All of the above

Question No# : 09 out of 50

What is the purpose of the "React.memo" function in React?

A. It is used to memoize function components for performance optimization

B. It is used to create custom hooks in React

C. It is used to manage state in class components

D. None of the above

Question No# : 10 out of 50

Which company developed ReactJS?

A. Apple

B. Facebook

C. Google

D. Twitter

Question No# : 11 out of 50

What is the role of a reducer in React?

A. It defines the initial state of a component

B. It determines the rendering of a component

C. It specifies the action types for handling user interactions

D. It manages the state transitions of a component based on dispatched actions

Question No# : 12 out of 50

What is the purpose of the "React.Fragment" component in React?

A. It is used to define the structure and layout of a React component

B. It is used to handle asynchronous operations and data fetching

C. It is used as a wrapper to render multiple elements without adding extra nodes to the DOM

D. None of the above

Question No# : 13 out of 50

How can you handle errors in React components?

A. By using the "try-catch" block in the component's render method

B. By using the "componentDidCatch" lifecycle method to catch and handle errors

C. By using global error handling provided by the browser

D. None of the above

Question No# : 14 out of 50

We can update the state in React.js by calling to setState() method. These calls are:

A. Synchronous in nature.

B. Asynchronous in nature.

C. Are asynchronous but can be made synchronous when required.

D. None of the above.

Question No# : 15 out of 50

What is the purpose of React's "Fragment" component?

A. It is used to wrap multiple components within a single parent component

B. It is used to conditionally render components based on certain conditionsIt is used to create reusable UI components in React

C. It is used to create reusable UI components in React

D. It is used to render multiple elements without adding extra nodes to the DOM

Question No# : 16 out of 50

What is the purpose of the "useEffect" hook in React?

A. To handle form validation in React components

B. To manage the lifecycle of functional components

C. To create custom hooks for reusable logic

D. To handle asynchronous operations in React components

Question No# : 17 out of 50

Which of the following is not a valid hook in React?

A. useState

B. useEffect

C. useData

D. useContext

Question No# : 18 out of 50

What is the significance of the "PureComponent" in React?

A. It is a component that can only render pure functions

B. It is a component optimized for performance by implementing a shallow comparison of props and state

C. It is a component designed for rendering complex UI elements

D. None of the above

Question No# : 19 out of 50

What is the concept of "code splitting" in React?

A. It is a technique to divide code into smaller modules for better performance and optimization

B. It is a way to write cleaner and more maintainable code in React applications

C. It is a technique to improve the rendering performance of React components

D. None of the above

Question No# : 20 out of 50

Which method in a React Component should you override to stop the component from updating?

A. willComponentUpdate

B. shouldComponentUpdate

C. componentDidUpdate

D. componentDidMount

Question No# : 21 out of 50

Why is ref used?

A. to bind the function

B. to call the function

C. to directly access the DOM node

D. to refer to another JS file

Question No# : 22 out of 50

In React, what is the purpose of the "defaultProps" property?

A. It specifies the default values for props in a component

B. It sets the initial state of a component

C. It defines the default styling for a component

D. It determines the default behavior of a component's lifecycle methods

Question No# : 23 out of 50

In which directory is react component saved?

A. vendor/js/components/

B. components/js

C. js/components

D. vendor/components

Question No# : 24 out of 50

Why is useLayoutEffect used?

A. To complete the update

B. To optimize for all devices

C. To change the layout of the screen

D. when you need the browser to paint before the effectors

Question No# : 25 out of 50

Why is the usage of set State?

A. Access the previous state before the set State operation

B. Replace the state completely instead of the default merge action

C. Invoke code after the set State operation is done

D. None

Question No# : 26 out of 50

How can you handle forms in React?

A. By using the controlled component pattern

B. By using the uncontrolled component pattern

C. By using form libraries like Formik or React Hook Form

D. All of the above

Question No# : 27 out of 50

What is the purpose of React's "StrictMode"?

A. To enforce strict code quality rules in React applications

B. To enable additional debugging checks and warnings in the development mode

C. To ensure compatibility with older versions of React

D. None of the above

Question No# : 28 out of 50

What is the purpose of the "React.StrictMode" component in React?

A. To enable additional debugging checks and warnings in the development mode

B. To enforce strict code quality rules in React applications

C. To ensure compatibility with older versions of React

D. To optimize rendering performance in React applications

Question No# : 29 out of 50

What is the purpose of React hooks like "useMemo" and "useCallback"?

A. To optimize the performance of functional components by memoizing values and functions

B. To manage the state of functional components

C. To handle side effects in functional components

D. None of the above

Question No# : 30 out of 50

What is true for the keys given to a list of elements in React?

A. Unique in the DOM.

B. Unique among the siblings only.

C. Do not require to be unique.

D. None of the above.

Question No# : 31 out of 50

What is JSX in React?

A. JavaScript XML

B. Java syntax extension

C. A templating language

D. None of the above

Question No# : 32 out of 50

React Lifecycle method static getDerivedSateFromProps(props , state) is called when ___

A. Component is created for the first time

B. State of the component is updated

C. Both A and B

D. None of the above

Question No# : 33 out of 50

What is the purpose of the "useReducer" hook in React?

A. To handle asynchronous operations and data fetching

B. To manage complex state and state transitions in functional components

C. To create reusable custom hooks

D. None of the above

Question No# : 34 out of 50

Arbitrary inputs of components in React are called

A. Keys

B. Props

C. Elements

D. Ref

Question No# : 35 out of 50

What is the purpose of React's "key" prop when rendering a list of elements?

A. It determines the order in which the list items are rendered

B. It ensures unique styling for each list item

C. It improves the performance of rendering the list

D. It helps React identify which items have changed, been added, or been removed

Question No# : 36 out of 50

What is the purpose of the "React.Fragment" shorthand syntax in React?

A. It is used to create a new React component

B. It is used to render multiple elements without adding extra nodes to the DOM

C. It is used to define the initial state of a component

D. It is used to manage the lifecycle of a component

Question No# : 37 out of 50

Does React.js create a VIRTUAL DOM in the memory?

A. True

B. False

C. Cannot say

D. None of above

Question No# : 38 out of 50

What is snapshot testing used for in react?

A. It allows us to test Javascript objects

B. It helps you write applications

C. It provides clear, enduring assertions

D. None of the above

Question No# : 39 out of 50

What is the purpose of React's "memo" function?

A. It is used to memoize function components for performance optimization

B. It is used to handle form validation in React components

C. It is used to create reusable custom hooks

D. It is used to define the structure and layout of a React component

Question No# : 40 out of 50

What is the purpose of state in React?

A. To store and manage data within a component

B. To define the structure of a React component

C. To handle user interactions in a component

D. To style the components

Question No# : 41 out of 50

In React, what is the purpose of the "setState" method?

A. To update the state of a component

B. To define the initial state of a component

C. To handle user interactions in a component

D. To render the component's UI

Question No# : 42 out of 50

Which of the following function is used to change the state of the React.js component?

A. this.setChangeState

B. this.State{}

C. this.setState

D. None of the above

Question No# : 43 out of 50

What is React context used for?

A. To pass data to deeply nested components without explicit prop drilling

B. To manage the global state of a React application

C. To enable communication between sibling components

D. All of the above

Question No# : 44 out of 50

What is the purpose of React's "Suspense" component?

A. To handle errors and fallback UI in React applications

B. To provide a way to lazy-load components and data in React applications

C. To handle form validation in React applications

D. None of the above

Question No# : 45 out of 50

How many numbers of elements a valid react component can return?

A. 2

B. 1

C. 4

D. 5

Question No# : 46 out of 50

What is the default port where web pack-server runs?

A. 8080

B. 6060

C. 3000

D. 3030

Question No# : 47 out of 50

In React, what is the purpose of the "useImperativeHandle" hook?

A. To handle form submissions in React components

B. To manage state in functional components

C. To expose certain methods of a child component to its parent component

D. To handle user interactions in React components

Question No# : 48 out of 50

What is the purpose of React's "useCallback" hook?

A. It is used to create reusable custom hooks in React

B. It is used to handle user interactions in React components

C. It is used to handle form submissions in React components

D. It is used to memoize functions for performance optimization

Question No# : 49 out of 50

What is the purpose of React's "getDerivedStateFromProps" lifecycle method?

A. It is used to handle form submissions in React components

B. It is used to manage state in functional components

C. It is used to update the state of a component based on changes in props

D. It is used to handle user interactions in React components

Question No# : 50 out of 50

How do you handle passing through the component tree without having to pass props down manually at every level?

A. React Send

B. React Pinpoint

C. React Router

D. React Context