Frequently Asked React Js Interview Questions And Answers
Common React.js Interview Questions and Answers
Frequently Asked React Js Interview Questions And Answers
React JS interview questions frequently cover core concepts like state management with hooks, functional components, and props passing. These questions assess candidates' understanding of React's declarative programming style, performance optimization techniques, and ability to work with complex components and data flows. By practicing these questions, candidates can showcase their knowledge of React's core principles and demonstrate their proficiency in building and maintaining scalable web applications.
To Download Our Brochure: https://www.justacademy.co/download-brochure-for-free
Message us for more information: +91 9987184296
1 - What's the purpose of React.js?
A front end library for building user interfaces.
2) Explain React's component lifecycle.
Mounting (created and rendered), Updating (state or props change), Unmounting (component removed from DOM).
3) What are the advantages of using React hooks?
Reduced boilerplate code, state and lifecycle management without class components.
4) What's the difference between state and props?
State is managed within the component, while props are passed in from the parent component.
5) Explain the concept of React Virtual DOM.
A lightweight representation of the DOM that allows React to efficiently update the UI.
6) What's the role of React Router?
Managing client side routing and providing navigation capabilities.
7) What are the best practices for optimizing React performance?
Use memoization, avoid unnecessary re renders, optimize component structure, and leverage third party performance tools.
8) Describe the difference between controlled and uncontrolled components.
Controlled components have their state managed by React, while uncontrolled components maintain their own state.
9) What's the purpose of Redux in React applications?
A state management library that provides centralized state management for complex applications.
10) How do you handle asynchronous operations in React?
Lifecycle methods, useEffect hook, promises, and async/await.
11 - What are some common debugging techniques for React applications?
Console logging, React Developer Tools, error boundaries, and source mapping.
12) Explain the concept of React Context.
A mechanism for sharing state between components without passing props through the entire component tree.
13) What's the difference between using inline and external styles in React?
Inline styles are added directly to a component's JSX, while external styles are defined in a separate CSS file.
14) Describe the role of Jest in testing React components.
A testing framework for unit and integration testing of React components.
15) What's the best way to handle prop validation in React?
Using propTypes, which are a set of predefined rules for props.
Strategies to Earn More Points:
1. Complete Surveys and Tasks:
- Sign up for survey panels like Swagbucks and MyPoints.
- * Participate in online surveys and complete tasks to accumulate points.
- 2. Shop with Partner Stores:
- * Check for retailers partnered with your rewards program.
- * Make purchases through those stores to earn points based on your spending.
- 3. Use Promotional Codes and Coupons:
- * Look for promo codes and coupons that offer bonus points or discounts.
- * Apply these codes when making purchases to maximize your earnings.
- 4. Refer Friends:
- * Most rewards programs offer referral bonuses.
- * Refer friends and family to join and they will typically earn you points once they sign up or make a purchase.
- 5. Connect Social Media Accounts:
- * Link your social media accounts to your rewards program.
- * Share posts, engage with content, and follow partner brands to earn extra points.
- 6. Participate in Contests and Giveaways:
- * Many rewards programs run contests and giveaways where you can win points.
- * Enter these contests to increase your chances of earning more.
- 7. Use Point Booster Tools:
- * Utilize browser extensions or apps that automatically track and boost your point earnings.
- * These tools can help you accumulate points faster.
- 8. Join VIP or Loyalty Programs:
- * Tiered loyalty programs offer higher point multipliers and exclusive perks for spending more.
- * Join VIP programs to accelerate your point accumulation.
- 9. Make Regular Purchases:
- * Consistently making purchases with your rewards card or using partner retailers will result in steady point accumulation.
- * The more you spend, the more points you earn.
- 10. Make Large Purchases:
- * Consider making large purchases with your rewards card.
- * These purchases can generate a significant amount of points, depending on the earning rate and spending threshold.
- Course Overview
- This course provides a comprehensive overview of frequently asked interview questions related to React JS, empowering candidates with the knowledge and confidence to excel in their interviews.
- Course Description
- This course provides comprehensive preparation for React JS job interviews by delving into frequently asked questions and equipping candidates with expert answers.
- Key Features
- 1 - Comprehensive Tool Coverage: Provides hands-on training with a range of industry-standard testing tools, including Selenium, JIRA, LoadRunner, and TestRail.
- 2) Practical Exercises: Features real-world exercises and case studies to apply tools in various testing scenarios.
- 3) Interactive Learning: Includes interactive sessions with industry experts for personalized feedback and guidance.
- 4) Detailed Tutorials: Offers extensive tutorials and documentation on tool functionalities and best practices.
- 5) Advanced Techniques: Covers both fundamental and advanced techniques for using testing tools effectively.
- 6) Data Visualization: Integrates tools for visualizing test metrics and results, enhancing data interpretation and decision-making.
- 7) Tool Integration: Teaches how to integrate testing tools into the software development lifecycle for streamlined workflows.
- 8) Project-Based Learning: Focuses on project-based learning to build practical skills and create a portfolio of completed tasks.
- 9) Career Support: Provides resources and support for applying learned skills to real-world job scenarios, including resume building and interview preparation.
- 10) Up-to-Date Content: Ensures that course materials reflect the latest industry standards and tool updates.
Benefits of taking our course
Functional Tools
1 - React Development Tools: Extension for Chrome and Firefox that provides deep insights into the React component hierarchy, performance, state management, and more.
2) React Router: Library for managing client side routing in React applications, allowing developers to define routes and navigate between different components based on URL changes.
3) Redux: State management library that provides a centralized store for application state, ensuring consistency and reducing boilerplate code.
4) GraphQL: Query language and runtime for fetching and modifying data from server side APIs in an efficient and type safe manner.
5) Jest and Enzyme: Testing frameworks for React applications, providing a comprehensive set of tools for unit testing, integration testing, and snapshot testing.
6) Immer: Immutability library that simplifies the handling of immutable data and state updates in React applications.
Earn Points by Playing Games
- Play the Daily Wheel for a chance to win up to 200 points.
- * Spin the Slot Machine for a chance to win up to 1,000 points.
- * Play Brain Games for a chance to win up to 500 points per game.
- Earn Points by Completing Surveys
- * Take surveys from trusted partners to earn points.
- * The length and complexity of the survey will determine the number of points you earn.
- Earn Points by Watching Videos
- * Watch short videos from trusted partners to earn points.
- * The length of the video will determine the number of points you earn.
- Earn Points by Referring Friends
- * Refer your friends to join the platform and earn points for each referral.
- * The number of points you earn per referral will vary depending on the program.
- Earn Points by Shopping
- * Shop through the platform's affiliate links to earn cashback points.
- * The amount of points you earn will vary depending on the store and the amount you spend.
- Earn Points by Completing Tasks
- * Participate in special tasks or promotions offered by the platform to earn extra points.
- * These tasks may include things like following social media accounts, downloading apps, or signing up for newsletters.
- Tips for Maximizing Points:
- * Check the platform regularly for new games, surveys, videos, and tasks.
- * Take advantage of bonuses and promotions that can increase your points earnings.
- * Refer as many friends as possible to earn bonus points.
- * Be consistent with your activity on the platform to earn points more frequently.
Browse our course links : https://www.justacademy.co/all-courses
To Join our FREE DEMO Session:
This information is sourced from JustAcademy
Contact Info:
Roshan Chaturvedi
Message us on Whatsapp:
Email id: info@justacademy.co
