Top 5 Interview Questions For Junior React Developers in 2022.

It's becoming increasingly difficult to choose the correct technology for a new app or website. React is one of the most rapidly expanding Javascript frameworks. There has been a steady rise in demand for React certification as JavaScript technologies have established themselves in the industry. React is a clear winner for front-end developers all around the world because of its short learning curve, reusable components, and clean abstraction. To help you with your interview preparation, we've compiled a list of some of the most common React interview questions and answers.

Let's take a look at five of the most common React Interview questions:

1. What are React's features?

2. What are the major differences between Real DOM and Virtual DOM? (Real Dom vs Virtual DOM)

3. How is React's ES6 syntax different from that of ES5 in terms of syntax?

When comparing ES5 to ES6, the following features of the syntax have been updated:

• importing vs. requiring

• export vs exports

• component and function

• props

• state

  
  

  Import vs. Requiring

  ES5 var React = require('react');

  ES6 import React from 'react';

Export vs Exports

ES5 module.exports = Component;

ES6 export default Component;

Component and Function

// ES5 Component
var MyComponent = React.createClass({
  render: function () {
    return <h3>Hello Edureka!</h3>;
  },
})
// ES6 Function
class MyComponent extends React.Component {
  render() {
    return <h3>Hello Edureka!</h3>
  }
}

Props

// ES5
var App = React.createClass({
  propTypes: { name: React.PropTypes.string },
  render: function () {
    return <h3>Hello, {this.props.name}!</h3>
  },
})
// ES6
class App extends React.Component {
  render() {
    return <h3>Hello, {this.props.name}!</h3>
  }
}

State

// ES5
var App = React.createClass({
  getInitialState: function () {
    return { name: 'world' }
  },
  render: function () {
    return <h3>Hello, {this.state.name}!</h3>
  },
})
// ES6
class App extends React.Component {
  constructor() {
    super()
    this.state = { name: 'world' }
  }
  render() {
    return <h3>Hello, {this.state.name}!</h3>
  }
}

4. List some of the most important benefits of using React in your essay.

React has a number of significant benefits, including the following:

• It improves the speed and responsiveness of the program.
• It is suitable for both the client and the server.
• The readability of code has improved as a result of JSX
• With React, additional frameworks like Meteor and Angular may be easily integrated.
• Writing UI test cases becomes a breeze with the help of React.

5. What are the reasons why browsers don't support JSX?

Only JavaScript objects are supported by browsers, but JSX is not one of them. For this reason, JSX files must first be converted into JavaScript objects like Babel before being sent to the browser.