React Interview Preparation Guide

Introduction

• The importance of knowing React concepts for interviews.
• Key topics and nuances in learning React.

1. Hooks

• Key Hooks to Know:
  • useState: Most widely used hook.
  • useEffect: Important; understand the dependency array.
    • Dependency array effects:
      • Empty array ([]): Runs once after initial render.
      • No dependency array: Runs after every render.
      • Values inside array: Runs when those values change.
  • Other Important Hooks:
    • useContext
    • useReducer
    • useMemo
    • useCallback
    • useRef
• Prepare and understand these hooks for interviews and daily coding.

2. Higher Order Components

• Understand:
  • What they are and why to use them.
  • Prepare to answer when, why, and how to use them, including examples and code.

3. Lifecycle Methods

• Focus mainly on class components, even if less common in modern React.
• Phases:
  • Mounting
  • Updating
  • Unmounting
• Know methods like componentDidMount, componentWillUnmount, etc.

4. State Management

• Understand state and props, including props drilling.
• Familiarize with React Context to manage props drilling issues.
• Libraries to Know:
  • Redux: Key state management library.
  • Zustand: Emerging alternative.
  • Redux Toolkit (RTK): Recommended for modern Redux usage.

5. Custom Hooks

• Importance of custom hooks in larger applications.
• Be able to write and explain custom hooks with examples.

6. Advanced Topics

• Lazy Loading: Important for performance optimization.
• Virtual DOM: Understanding reconciliation algorithm and React Fiber.

7. Server-Side Rendering (SSR) vs Client-Side Rendering (CSR)

• Know the definitions, differences, and advantages of each.
• Impact on SEO and performance.

8. Routing and Role-Based Access Control (RBAC)

• Importance of handling routes and protected routes.
• Use libraries like React Router for managing routes.

9. Testing

• Importance of writing tests in your applications.
• Familiarize with React Testing Library.
• Mentioning testing in interviews can make a strong impression.

10. Async Tasks

• Understand how to make API calls and handle asynchronous tasks.
• Know about promises and their usage in JavaScript.

11. Reusability, Modularity, and Testability

• Key coding practices to highlight during interviews.
• Importance of writing clean, maintainable code.

12. Performance

• Major focus for senior developers.
• Topics include:
  • Asset optimization
  • Lazy loading
  • Bundle optimization
  • Shimmer UI concepts.

13. Styling

• Understand various styling methods (e.g., Tailwind, Bootstrap, Material UI).
• Pros and cons of each method; ability to reason choices in interviews.

14. Accessibility

• Importance in modern web applications.
• Knowledge of accessibility practices can earn brownie points in interviews.

Conclusion

• Emphasize the importance of preparing these topics for interviews.
• Online resources and courses can aid in learning (e.g., Namaste React).
• Encourage practice and self-study for a thorough understanding.