Accenture React Js Frontend Developer Interview Questions, Process, and Tips for Experienced

Virtual DOM is a lightweight copy of the actual DOM that React uses to improve performance by minimizing direct manipulation of the actual DOM.

• Virtual DOM is a representation of the actual DOM in the form of a lightweight copy.

• When changes are made to the virtual DOM, React compares it with the actual DOM to identify the minimal number of changes needed.

• This process helps in optimizing performance by reducing direct ma...read more

Reconciliation in React is the process of updating the DOM to match the virtual DOM.

• Reconciliation is the algorithm that React uses to update the UI efficiently.

• It compares the virtual DOM with the previous virtual DOM and only updates the necessary components.

• Reconciliation helps in improving performance by minimizing DOM manipulations.

• Key prop is important for reconciliation to identify which items have changed, adde...read more

Closures are functions that have access to variables from their outer scope even after the outer function has finished executing.

• Closures allow functions to access variables from their parent function's scope

• They maintain a reference to the variables they need, even after the parent function has finished executing

• Closures are commonly used in event handlers and callbacks

Hoisting is a JavaScript mechanism where variable and function declarations are moved to the top of their containing scope during compilation.

• Hoisting applies to both variable and function declarations.

• Variable declarations are hoisted to the top of their scope but not their assignments.

• Function declarations are fully hoisted, meaning they can be called before they are declared.

ES6 features are modern JavaScript syntax enhancements that make code more concise and readable.

• Arrow functions for more concise syntax: const add = (a, b) => a + b;

• Let and const for block-scoped variables: let x = 5; const y = 10;

• Template literals for string interpolation: const name = 'Alice'; console.log(`Hello, ${name}!`);

• Destructuring assignment for easily extracting values from objects or arrays: const { firstNam...read more

React Fiber is a complete rewrite of React's core algorithm for rendering UI components.

• React Fiber is a reimplementation of the React core algorithm.

• It allows for incremental rendering, prioritizing updates based on their priority level.

• Fiber reconciles the virtual DOM tree in a more efficient and flexible way.

• It enables features like error boundaries, async rendering, and more.

• Fiber was introduced in React version 16

Implementing dark mode in an application involves changing the color scheme to darker tones for better visibility in low light environments.

• Use CSS variables to define color schemes for light and dark modes

• Toggle between light and dark mode using a state variable in React

• Apply the appropriate color scheme based on the selected mode

• Allow users to switch between light and dark mode using a toggle button

Hooks are a feature in React that allow you to use state and other React features in functional components.

• Hooks were introduced in React 16.8.

• They allow you to use state and other React features without writing a class component.

• Commonly used hooks include useState, useEffect, useContext, and useReducer.

• Hooks must be used at the top level of a functional component.

• Hooks can be custom created as well.

Life cycle methods are methods that are called at different stages of a component's life cycle in React.

• Mounting phase: constructor, render, componentDidMount

• Updating phase: shouldComponentUpdate, render, componentDidUpdate

• Unmounting phase: componentWillUnmount

State is mutable and managed within a component, while props are immutable and passed from parent to child components.

• State is managed within a component and can be changed using setState() method

• Props are passed from parent to child components and cannot be changed within the child component

• State is used for internal component data management, while props are used for passing data from parent to child components

React is a JavaScript library for building user interfaces, while JavaScript is a programming language used for web development.

• React is a library for building user interfaces, while JavaScript is a programming language.

• React uses a virtual DOM for faster rendering, while JavaScript directly manipulates the DOM.

• React allows for component-based architecture, while JavaScript is more procedural in nature.

• React provides a...read more

ReactJS is popular for its virtual DOM, component-based architecture, and strong community support.

• React's virtual DOM allows for efficient updates and improved performance.

• Component-based architecture promotes reusability and maintainability of code.

• React has a large and active community, providing extensive resources and support.

• React's JSX syntax makes it easier to write and understand code compared to other framewo