React JS Interview Insight: React JS is like the e-commerce of web development. It’s dynamic, fast, and has great user experience. Handling state is like keeping the front-end content fresh, and splitting code using lazy loading is like managing demand and supply. React hooks are the wizardry that makes your app rock the charts. So forget Angular, and embrace the React revolution! π
π Introduction
In this comprehensive collection of top 100 React JS interview questions and answers, we will cover fundamental concepts, syntax, and features of React JS.
π Concepts Covered
Basic Concepts
React JS is a front-end, dynamic, open-source JavaScript library. It is the foundation for building user interfaces, specifically single-page applications. In React JS, the manipulation and updating of the Document Object Model (DOM) are done through a virtual DOM.
JSX Syntax
JSX is a syntax extension for JavaScript, recommended by React for writing UI components. It allows HTML-like code to be written within JavaScript.
Declarative Syntax
React JS provides a declarative syntax to display UI components. It allows developers to write a more predictable and bug-free code.
π Key Takeaways
| Concept | Description |
|---|---|
| Advantage of React | React JS is fast and efficient in rendering web pages, making it a popular choice for web development. |
| JSX Syntax | JSX syntax is a feature of React JS that enables the mixing of HTML-like syntax within JavaScript. |
| React Components | React applications are built using reusable and independent components, promoting code reusability.
| Virtual DOM | React JS uses a virtual representation of the DOM to improve performance and efficiency in updating the actual DOM.|
β‘οΈ Understanding Components
Functional vs Class Components
Functional components in React JS are purely JavaScript-based and are easier to read and test. Class components require the use of the class keyword and are more feature-rich.
Props and State
Props and state are important concepts in React JS. Props are read-only data that are passed from the parent component, while state is used for managing component-local data, and can be changed using setState().
βοΈ Conclusion
In conclusion, React JS is a powerful library for web development, offering benefits such as fast rendering and component reusability. Understanding the concepts covered in this article will help you prepare for React JS interviews.
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