QUIZ ON : react - MISCELLANEOUS

MISCELLANEOUS

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Question No# : 01 out of 50

In React, what is the purpose of the "forwardRef" function?

A. To create higher-order components (HOCs) that forward props to child components

B. To create reusable custom hooks

C. To forward the ref from a parent component to a child component

D. None of the above

Question No# : 02 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# : 03 out of 50

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

A. Asynchronous in nature

B. Synchronous in nature

C. Are asynchronous but can be made synchronous when required

D. None of the these

Question No# : 04 out of 50

Which of the following is the correct name of React.js?

A. React.js

B. React

C. ReactJS

D. All of the above

Question No# : 05 out of 50

What is React Hooks in React?

A. A way to create reusable logic in functional components

B. A replacement for class components in React

C. A mechanism to manage state and lifecycle in functional components

D. All of the above

Question No# : 06 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# : 07 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# : 08 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# : 09 out of 50

In which of the following directory React.js components are saved?

A. Inside the vendor/components/

B. Inside the vendor/

C. Inside the js/components/

D. Inside the external/components/

Question No# : 10 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# : 11 out of 50

In React, what is the purpose of the "forwardRef" function?

A. In React, what is the purpose of the "forwardRef" function?

B. It is used to forward props to child components

C. It is used to forward a ref to a child component

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

Question No# : 12 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# : 13 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# : 14 out of 50

Choose the library which is most often associated with react?

A. Sinon

B. Chai

C. Jest

D. Mocha

Question No# : 15 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# : 16 out of 50

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

A. 8080

B. 6060

C. 3000

D. 3030

Question No# : 17 out of 50

What is the significance of the "key" prop in React lists?

A. It improves the performance of rendering lists

B. It ensures that the list items are displayed in alphabetical order

C. It uniquely identifies each element in a list, aiding in efficient updates

D. It controls the styling of list items

Question No# : 18 out of 50

How can you access the state of a component from inside of a member function?

A. this.state

B. this.values

C. this.getState()

D. this.prototype.stateValue

Question No# : 19 out of 50

What is the concept of React portals?

A. It is a way to create reusable UI components in React

B. It is a mechanism to optimize rendering performance in React

C. It is a way to render React components outside of their parent component's DOM hierarchy

D. None of the above

Question No# : 20 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

Question No# : 21 out of 50

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

A. 2

B. 1

C. 4

D. 5

Question No# : 22 out of 50

What is the significance of React's "virtual DOM"?

A. It is a way to optimize rendering performance in React applications

B. It is a mechanism to handle errors and fallback UI in React applications

C. It is a technique to render React components outside of their parent component's DOM hierarchy

D. It is a representation of the actual DOM in memory, allowing efficient updates and rendering

Question No# : 23 out of 50

What is the use of “web pack” command in React.js?

A. It is a module bundler

B. The “webpack” command is used to transpile all the JavaScript down into one file

C. It runs React local development server

D. None of the above

Question No# : 24 out of 50

What helps react for keeping their data unidirectional.?

A. JSX

B. Props

C. Flux

D. DOM

Question No# : 25 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# : 26 out of 50

What is the purpose of React's "Context.Consumer" component?

A. It is used to create a context object for sharing data across components

B. It is used to consume the context value provided by a "Context.Provider" component

C. It is used to render conditional content in React components

D. It is used to optimize the rendering performance of React components

Question No# : 27 out of 50

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

A. It is used to manage state in functional components

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

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

D. It is used to optimize the rendering performance of React components

Question No# : 28 out of 50

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

A. useState

B. useEffect

C. useData

D. useContext

Question No# : 29 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# : 30 out of 50

In relation to React js component lifecycle, which statement is true

A. Only function component can have life cycle

B. Only class components can have life cycle

C. Both type of components can have life cycle

D. None of above

Question No# : 31 out of 50

When is useReducer used over useState in React component?

A. When we want to replace redux

B. When we want to break our production app

C. When we want to improve performance

D. none of the above

Question No# : 32 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# : 33 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# : 34 out of 50

In react, the key should be?

A. Unique among his siblings only

B. Unique in the DOM

C. Does not requires to be unique

D. all of the above

Question No# : 35 out of 50

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

A. To manage state in functional components

B. To handle form submissions in React components

C. To create a reference to an element or value in a functional component

D. To handle asynchronous operations and data fetching

Question No# : 36 out of 50

What changes would appear in the component as soon as the state of the React component is changed?

A. It will re-render the component

B. It can be created again from scratch

C. It will do nothing; you have to call render method to render the component again

D. None

Question No# : 37 out of 50

What is the purpose of React's "setState" method when called with a function as an argument?

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

B. It is used to handle user interactions in a component

C. It is used to update the state of a component based on the previous state

D. It is used to render the component's UI

Question No# : 38 out of 50

Which of the following option is correct in the case of the Babel?

A. Babel is a Transpolar

B. Babel is a Compiler

C. All of above

D. None of above

Question No# : 39 out of 50

What is the purpose of keys in React lists?

A. To uniquely identify elements in a list

B. To define the layout and styling of list items

C. To handle event listeners on list items

D. None of the above

Question No# : 40 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# : 41 out of 50

What is the purpose of the React Developer Tools extension?

A. It allows developers to inspect the component hierarchy and state in a React application

B. It provides a code editor specifically designed for writing React components

C. It enables real-time collaboration among multiple developers working on a React project

D. It automatically generates documentation for React components

Question No# : 42 out of 50

Which company developed ReactJS?

A. Apple

B. Facebook

C. Google

D. Twitter

Question No# : 43 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# : 44 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# : 45 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# : 46 out of 50

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

A. To handle form submissions in React components

B. To manage state in functional components

C. To handle navigation in React applications

D. To provide access to the context value in functional components

Question No# : 47 out of 50

Which method is used to change the state of a component in React?

A. setState()

B. changeState()

C. updateState()

D. modifyState()

Question No# : 48 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# : 49 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# : 50 out of 50

What is the purpose of React's "render props" pattern?

A. It is a technique to render HTML elements in React components

B. It is a way to pass a function as a prop to a component for rendering dynamic content

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

D. It is a way to handle user interactions in React components