If you’re preparing for a React.js interview at American Express, it’s essential to be well-versed with the core concepts of React, as well as related technologies and best practices. In this blog, we’ll cover some common interview questions you might encounter and provide insights into what interviewers might be looking for.
Tip for Readers: Pay particular attention to the React questions, as they were more focused and in-depth. However, a solid understanding of JavaScript fundamentals is also essential.
JavaScript Questions
- What are side-effects?
- What does the fetch API method return and why do we use response.json()?
- Explain closures in JavaScript.
- Is Redux synchronous or asynchronous?
- Which has higher priority in the event loop: fetch or setTimeout?
- Is JavaScript synchronous or asynchronous?
- Create a higher order function similar to array.map.
React Questions
- How is closure used in React?
- Lifecycle methods in React.
- Context API in React.
- Write a custom memoize function in React.
- Optimization techniques used in React.
- Features of React 18.
- Error Boundaries in React and How to create them
Conclusion
These questions covered a broad range of topics, testing both theoretical knowledge and practical skills in JavaScript and React. Focusing on understanding the intricate details of React will likely be more beneficial, given the emphasis on this during the interview.
Feel free to share your own experiences or additional questions you’ve encountered in React.js interviews in the comments below.
