ReactJS Technical Questions – codewindow.n

ReactJS - Questions

Introduction

Components in React.js

Virtual DOM in React.js

State and Props in React.js

React Router

React with Webpack and Babel

Testing in React.js

Related Topics

ReactJS - Questions

1. What is React and why is it important in front-end development?

2. What are the main differences between React and other JavaScript frameworks and libraries?

3. What is the virtual DOM and how does it improve performance in React?

4. Explain how components and props work in React?

5. What is state and how is it managed in React?

6. How does React handle updates and re-rendering of components?

7. What are the lifecycle methods of a React component?

8. What is the role of JSX in React and how does it make writing components easier?

9. What is the purpose of the React Router library and how is it used?

10. How to handle data management and API calls in React?

11. What are Higher-Order Components and how are they used in React?

12. How does React handle performance optimization and updates to the virtual DOM?

13. Discuss the concept of server-side rendering in React?

14. How does React handle cross-browser compatibility issues?

15. What is Redux and how does it integrate with React?

16. What is a React component and how is it different from a plain JavaScript function or class?

17. How to create a stateless or stateful component in React?

18. Explain the difference between props and state in React?

19. How to pass data from a parent component to a child component in React?

20. How to manage component state and lifecycle methods in React?

21. Explain the use of key prop in React components?

22. How to handle events in React components?

23. Explain the concept of Virtual DOM in React and its benefits?

24. What are Higher-Order Components in React and how to use them?

25. How to debug React components in the browser?

26. Explain how React uses the concept of immutability to improve performance?

27. How to use conditional rendering in React components?

28. Explain what the Virtual DOM is in React.js and why it’s used?

29. How does React’s Virtual DOM improve performance compared to manipulating the actual DOM directly?

30. Give an example of how React updates the Virtual DOM?

31. How does React determine which components in the Virtual DOM need to be updated?

32. Explain the difference between the Virtual DOM and the Real DOM?

33. Explain how React’s Virtual DOM helps improve SEO?

34. How does React’s Virtual DOM make it easier to debug and test applications?

35. Explain how React’s Virtual DOM optimizes updates and renders in a fast and efficient manner?

36. How does React use the Virtual DOM to handle state changes in an application?

37. How does React use the Virtual DOM to handle state changes in an application?

38. What is the difference between state and props in React.js?

39. How to update the state in React.js and what is the use case for it?

40. What is the significance of props in React.js and how are they passed down to child components?

41. Explain the concept of immutability in the context of state and props in React.js?

42. How does React.js handle updates to its components when the state or props change?

43. Give an example of when you would use state in your React.js application and when you would use props?

44. How does the use of state and props affect the performance of a React.js application?

45. Discuss the concept of “lifting state up” in React.js and why it is important?

46. What are some best practices for managing the state in a React.js application?

47. How to ensure that state updates in a React.js application are performed in a predictable and efficient manner?

48. What is React Router and how is it used in React applications?

49. What are the different types of routing in React Router (e.g. URL routing, component routing)?

50. How to handle nested routes in React Router?

51. What is the use of the “Switch” component in React Router and when would you use it?

52. Explain the concept of URL parameters in React Router and how to use them in your applications?

53. What is the difference between the use of the “Link” and “NavLink” components in React Router?

54. How to handle redirects in React Router and what is the purpose of the “Redirect” component?

55. Explain the process of programmatic navigation in React Router and how it is used in your applications?

56. What are the security concerns when using React Router and how can they be addressed?

57. How to dynamically update the URL in React Router based on user actions or other events in your application?

58. Explain what React Hooks are and how they differ from HOCs and render props?

59. How to use the useState hook in a React component?

60. Example of how to use the use Effect hook to manage side effects in a React component?

61. Explain the difference between use Effect and use Layout Effect?

62. How to implement a custom hook in React?

63. Explain the use of the use Context hook in React?

64. How to manage the value of a controlled form input using the useState and useEffect hooks in React?

65. Give an example of how you would implement the useReducer hook in React?

66. Explain the use of the useRef hook in React?

67. Explain the difference between useRef and useState in React?

68. What is Redux and why is it used in React.js?

69. What is the difference between state and props in React and how does Redux handle state management?

70. Explain the concept of “state management” in React and how Redux helps with it?

71. How does the Redux store, actions, and reducers work together in a React application?

72. What are some common use cases for using Redux in a React application?

73. Give an example of how to handle asynchronous actions in a Redux store?

74. How does Redux handle data normalization in a React application?

75. What are the benefits of using Redux middleware in a React application?

76. How to debug a Redux store in a React application?

77. Explain the concept of “reselect” library in Redux and when to use it?

78. How to handle updating the Redux store when your React components re-render?