MERN Stack Live Beginner Interview | Real Questions & Answers #mernstack

Summary

In this interview, Ashish Mishra, a full-stack developer, discusses his experience with the MERN stack, including MongoDB, Express, React, and Node.js. He explains key React concepts such as components, hooks, props, state, and routing. He also addresses the usage of libraries like Redux and React Router, and highlights the importance of API integration and local storage. Ashish provides insights into managing complex applications with different user roles and layouts. Throughout the conversation, he demonstrates his proficiency in front-end development and practical approaches to React app integration, emphasizing both technical knowledge and hands-on experience.

Takeaways

• 😀 Ashish Mishra is a graduate in Bachelor of Computer Applications and currently works as a full-stack developer in an IT company.
• 😀 Montech is a full-stack technology stack consisting of MongoDB, Express.js, React, and Node.js, used for creating web applications.
• 😀 Express.js helps in connecting the MongoDB database to the front-end and is used for creating APIs and handling routing.
• 😀 React components are JavaScript functions that return JSX. Every React app must have at least one component, usually `App.js`.
• 😀 React hooks, introduced in version 16.8, simplify state management and side-effect handling within functional components.
• 😀 State is used for managing dynamic data and changing values within a React app, while props are used to pass data from parent to child components.
• 😀 Stateful components manage their own state, while stateless components only receive and display data without handling state.
• 😀 Props can be passed as objects to child components and can be destructured for easier use in functional components.
• 😀 React's `useContext` hook and third-party libraries like Redux can be used for managing and passing data across multiple components.
• 😀 React Router DOM is used for handling navigation between different views in a React app, and `Link` is used for creating hyperlinks.
• 😀 Local storage in React is used to store temporary data, such as login information, in the browser for easy access across sessions.
• 😀 Ashish has created React applications such as a to-do list and rental service search features, showcasing practical experience with React development.
• 😀 Bootstrap can be integrated into a React project either via a CDN or by installing it via npm for styling components.

Q & A

What is the role of ExpressJS in the MERN stack?

ExpressJS acts as the backend framework in the MERN stack, helping to connect MongoDB with the frontend and facilitating the creation of APIs and routing for web applications.

What is a component in React, and why is it important?

A component in React is a JavaScript function that returns JSX. It is essential because it allows developers to build reusable, modular parts of a web application, making the app more maintainable and scalable.

What is the difference between state and props in React?

State is used to track changes and manage data within a component, whereas props are used to pass data from parent to child components. State is mutable within a component, while props are immutable and cannot be changed by the child component.

What is the purpose of hooks in React?

Hooks were introduced in React 16.8 to simplify state management and side effects in functional components. They allow developers to manage state, perform operations like fetching data, and handle lifecycle events without using class components.

Can hooks be used in class components?

No, hooks cannot be used in class components. Class components use their own state management and lifecycle methods, whereas hooks are specifically designed for use in functional components.

What is the use of the `useContext` hook in React?

The `useContext` hook allows you to access values from a React context and manage global state across different components without passing props manually. This is useful for state that needs to be shared between many components.

How do you pass multiple values using props in React?

Multiple values can be passed through props by using an object to group the values together. In the child component, you can destructure the object to access each individual value.

What is the main difference between stateful and stateless components in React?

Stateful components manage their own internal state, making them suitable for interactive parts of an app. Stateless components, on the other hand, do not manage state and are used to display data passed from parent components.

How do you handle routing in a React application with different layouts for different user roles (e.g., admin and customer)?

To handle routing with different layouts, you can create multiple layout components (e.g., an admin layout and a customer layout). Then, use React Router to define routes that render the appropriate layout based on the user’s role.

What is the difference between `fetch()` and `axios` for making API requests in React?

While both `fetch()` and `axios` are used to make API requests, `axios` is often preferred because it simplifies the process by automatically parsing JSON responses and handling errors. `fetch()` requires more manual configuration, like checking for response success and parsing JSON.