Premium Employer

i

This company page is being actively managed by iEnergizer Team. If you also belong to the team, you can get access from here

iEnergizer Verified Tick

Compare button icon Compare button icon Compare

Filter interviews by

Clear (1)

iEnergizer Front end Developer Interview Questions and Answers

Updated 15 Jan 2025

iEnergizer Front end Developer Interview Experiences

1 interview found

Interview experience
4
Good
Difficulty level
Moderate
Process Duration
Less than 2 weeks
Result
Not Selected

I applied via Naukri.com and was interviewed in Dec 2024. There were 3 interview rounds.

Round 1 - Coding Test 

Coding test was the first round of interview

Round 2 - Technical 

(1 Question)

  • Q1. What is virtual dom in react and what makes it faster ?
  • Ans. 

    Virtual DOM is a lightweight copy of the actual DOM in React, allowing for efficient updates and rendering.

    • Virtual DOM is a representation of the actual DOM in memory.

    • React compares the virtual DOM with the actual DOM to identify changes.

    • Only the differences between the virtual and actual DOM are updated, making it faster.

    • Example: When a user interacts with a React component, the virtual DOM is updated first before the

  • Answered by AI
Round 3 - One-on-one 

(1 Question)

  • Q1. It was HR round

Interview questions from similar companies

I was interviewed before Dec 2020.

Round 1 - Coding Test 

(1 Question)

Round duration - 360 minutes
Round difficulty - Medium

Basically TCS conduct its flagship event named as CODEVITA . And it offers Internship to prefinal (3rd )year students .

  • Q1. 

    Allocate Books Problem Statement

    Given an array of integers arr, where arr[i] represents the number of pages in the i-th book, and an integer m representing the number of students, allocate all the books ...

  • Ans. 

    Allocate books to students in a way that minimizes the maximum number of pages assigned to a student.

    • Iterate through possible allocations and calculate the maximum pages assigned to a student.

    • Find the minimum of these maximums to get the optimal allocation.

    • Return the minimum pages allocated in each test case, or -1 if not possible.

  • Answered by AI

Interview Preparation Tips

Eligibility criteriaMust be doing B.TECHTata Consultancy Services (TCS) interview preparation:Topics to prepare for the interview - Data Structure , Algorithms ,DBMS , OOPs ,OSTime required to prepare for the interview - 2 MonthsInterview preparation tips for other job seekers

Tip 1 : Good understanding of Data Structure and Algorithms 
Tip 2 : Be clear in your Core Subjects.
Tip 3 : Do at least 1 good Project .
Tip 4 : Be humble and speak truth .

Application resume tips for other job seekers

Tip 1 : Simple and Crisp .
Tip 2 : Do host your project and mention the link in the resume .
Tip 3 : Single Page

Final outcome of the interviewSelected

Skills evaluated in this interview

Interview experience
3
Average
Difficulty level
Moderate
Process Duration
Less than 2 weeks
Result
No response

I applied via Naukri.com and was interviewed in Mar 2024. There was 1 interview round.

Round 1 - Technical 

(14 Questions)

  • Q1. Let var const in JavaScript
  • Ans. 

    var and const are used to declare variables in JavaScript, with var being mutable and const being immutable.

    • var is used to declare variables that can be reassigned and updated

    • const is used to declare variables that cannot be reassigned or updated

    • let is another keyword used for declaring variables, similar to var but with block scope

  • Answered by AI
  • Q2. Error boundary and how to handle
  • Ans. 

    Error boundary is a React component that catches JavaScript errors anywhere in a component tree and logs those errors.

    • Error boundaries are React components that catch JavaScript errors in their child component tree.

    • They are used to prevent the entire UI from crashing due to a single error.

    • Error boundaries work like a JavaScript catch {} block, but for components.

    • They are defined using componentDidCatch lifecycle method

  • Answered by AI
  • Q3. Event.bind and event.property
  • Q4. Use of never in typescript
  • Ans. 

    The 'never' type in TypeScript represents a value that will never occur.

    • Used to indicate that a function will not return a value

    • Commonly used in union types to exclude certain values

    • Helps catch potential errors at compile time

  • Answered by AI
  • Q5. What hooks you have used
  • Ans. 

    I have used React hooks such as useState, useEffect, useContext, and useRef in my projects.

    • useState

    • useEffect

    • useContext

    • useRef

  • Answered by AI
  • Q6. What is difference between use reducer and use state
  • Ans. 

    useReducer is preferred for managing complex state logic, while useState is simpler for basic state management.

    • useReducer is more suitable for managing complex state logic and multiple state values

    • useState is simpler and more straightforward for basic state management with a single value

    • useReducer allows for more organized and centralized state updates through actions and reducers

    • useState is commonly used for simple co

  • Answered by AI
  • Q7. Why we use state and props
  • Q8. How you will pass data from parent to child
  • Ans. 

    Data can be passed from parent to child components in React using props.

    • Pass data as props from parent component to child component

    • Use state management libraries like Redux or Context API for complex data sharing

    • Use callback functions to pass data from child to parent components

  • Answered by AI
  • Q9. Write your own custom hook
  • Ans. 

    Custom hook to fetch data from an API

    • Create a function that uses the useState and useEffect hooks

    • Use the fetch API to make a request to the desired endpoint

    • Return the fetched data and loading state in an array

  • Answered by AI
  • Q10. Explain map filter and reduce functions
  • Ans. 

    Map, filter, and reduce are higher-order functions in JavaScript used to manipulate arrays.

    • Map: Transforms each element in an array and returns a new array with the transformed elements.

    • Example: [1, 2, 3].map(num => num * 2) returns [2, 4, 6].

    • Filter: Returns a new array with elements that pass a certain condition.

    • Example: [1, 2, 3].filter(num => num > 1) returns [2, 3].

    • Reduce: Applies a function against an accumulator ...

  • Answered by AI
  • Q11. How you can clone an object
  • Ans. 

    To clone an object in JavaScript, you can use the spread operator or Object.assign() method.

    • Use the spread operator to create a shallow copy of an object: const clonedObj = { ...originalObj };

    • Use Object.assign() method to create a shallow copy of an object: const clonedObj = Object.assign({}, originalObj);

    • For deep cloning, you can use libraries like Lodash or write a custom function to recursively clone nested objects.

  • Answered by AI
  • Q12. What are the three stages of event propagation and how to handle it
  • Ans. 

    Event propagation consists of three stages: capturing, target, and bubbling.

    • Capturing phase: Events are captured from the outermost element to the target element.

    • Target phase: Event reaches the target element where the event originated.

    • Bubbling phase: Events bubble up from the target element to the outermost element.

  • Answered by AI
  • Q13. How to handle errors in your react application
  • Ans. 

    Errors in a React application can be handled by using error boundaries, try-catch blocks, and displaying error messages to users.

    • Use error boundaries to catch errors in components and display a fallback UI

    • Wrap code that may throw errors in try-catch blocks to handle exceptions

    • Use libraries like React Error Boundary to easily implement error handling

    • Display error messages to users to inform them about the issue and poss

  • Answered by AI
  • Q14. Write code to call fake api and display the title where category is “some category “

Skills evaluated in this interview

I applied via Approached by Company and was interviewed in Feb 2022. There was 1 interview round.

Round 1 - Technical 

(1 Question)

  • Q1. Basics of react and JavaScript

Interview Preparation Tips

Interview preparation tips for other job seekers - Try to Give examples Supporting your answers
Interview experience
5
Excellent
Difficulty level
Easy
Process Duration
Less than 2 weeks
Result
-

I applied via Naukri.com and was interviewed in Nov 2022. There were 3 interview rounds.

Round 1 - Resume Shortlist 
Pro Tip by AmbitionBox:
Keep your resume crisp and to the point. A recruiter looks at your resume for an average of 6 seconds, make sure to leave the best impression.
View all Resume tips
Round 2 - Aptitude Test 

An aptitude test is a way for employers to assess a candidate's abilities through a variety of different testing formats. Aptitude tests will test your ability to perform tasks and react to situations at work. This includes problem-solving, prioritisation and numerical skills, amongst other things.

Round 3 - Assignment 

An assignment is the transfer of rights or property. In financial markets, it is a notice to an options writer that the option has been exercised.

Interview Preparation Tips

Interview preparation tips for other job seekers - Finding a job is easier said than done. While you may know to submit a professional résumé, write a thoughtful cover letter and practice before an interview, sometimes you still don't get the job.

While every job-search experience is different, it's helpful to hear from others who are in or have been in the same boat as you. Here, experts and past job seekers share some of their best advice for landing your dream role:
Interview experience
5
Excellent
Difficulty level
Easy
Process Duration
Less than 2 weeks
Result
-

I applied via Naukri.com and was interviewed in Feb 2024. There were 3 interview rounds.

Round 1 - Technical 

(4 Questions)

  • Q1. What is react and it's advantage
  • Ans. 

    React is a JavaScript library for building user interfaces.

    • React allows for the creation of reusable UI components

    • It uses a virtual DOM for efficient rendering

    • React is declarative, making it easier to understand and debug code

  • Answered by AI
  • Q2. React life cycle
  • Q3. Questions related to Redux
  • Q4. Simple app using redux
  • Ans. 

    Creating a simple app using Redux for state management in a front end application.

    • Set up Redux store with reducers and actions

    • Connect components to Redux store using mapStateToProps and mapDispatchToProps

    • Dispatch actions to update state in Redux store

    • Use combineReducers to manage multiple reducers

  • Answered by AI
Round 2 - One-on-one 

(2 Questions)

  • Q1. Previous project
  • Q2. Agile process followed in project
  • Ans. 

    Agile process involves iterative development, frequent collaboration, and adaptability to changes.

    • Daily stand-up meetings to discuss progress and roadblocks

    • Sprints for focused development and testing

    • Continuous feedback and iteration based on user input

    • Use of tools like Jira or Trello for project management

  • Answered by AI
Round 3 - HR 

(2 Questions)

  • Q1. Salary discussion
  • Q2. Work location discussion

Interview Preparation Tips

Interview preparation tips for other job seekers - Strong in basics and coding

Skills evaluated in this interview

I applied via LinkedIn

Interview Questionnaire 

5 Questions

  • Q1. 1.what is strict Mode in react. 2.Virtual Dom. 3,react and html difference
  • Q2. What is redux
  • Ans. 

    Redux is a predictable state container for JavaScript apps.

    • Redux is a library for managing application state

    • It provides a centralized store for all the state of an application

    • It uses a single source of truth principle

    • It allows for predictable state changes through actions and reducers

    • It is commonly used with React for building complex UIs

  • Answered by AI
  • Q3. What is jquery? 2.explain architecture of your project.
  • Ans. 

    jQuery is a fast, small, and feature-rich JavaScript library.

    • jQuery simplifies HTML document traversing, event handling, and animating.

    • It provides a set of methods for AJAX interactions and DOM manipulation.

    • jQuery is cross-platform and supports a wide range of browsers.

    • It has a large community and a vast number of plugins available.

    • Project architecture depends on the specific project and its requirements.

  • Answered by AI
  • Q4. Form validation in react
  • Ans. 

    Form validation in React ensures user input is correct before submission.

    • Use controlled components to manage form state

    • Create validation functions to check input

    • Display error messages for invalid input

    • Disable submit button until form is valid

    • Consider using a library like Formik or Yup for easier validation

  • Answered by AI
  • Q5. React hooks explanation
  • Ans. 

    React hooks are functions that allow functional components to use state and lifecycle methods.

    • Hooks were introduced in React 16.8

    • useState() is a hook that allows state to be used in functional components

    • useEffect() is a hook that allows lifecycle methods to be used in functional components

    • Custom hooks can be created to reuse stateful logic across components

  • Answered by AI

Interview Preparation Tips

Interview preparation tips for other job seekers - Make sure u have entered proper information in your resume,mostly they asked the questions related to previous projects working and the technologies which we had mentioned in resume, always study own resume and prepare accourding to that.

Skills evaluated in this interview

Interview experience
4
Good
Difficulty level
-
Process Duration
-
Result
-
Round 1 - Technical 

(1 Question)

  • Q1. Reverse the string
  • Ans. 

    Reverse a given string

    • Use built-in methods like split(), reverse(), and join() to reverse the string

    • Alternatively, loop through the string from end to start and build a new reversed string

  • Answered by AI

Skills evaluated in this interview

Interview experience
3
Average
Difficulty level
Moderate
Process Duration
Less than 2 weeks
Result
No response

I applied via Naukri.com and was interviewed in Mar 2024. There were 2 interview rounds.

Round 1 - Technical 

(1 Question)

  • Q1. Reverse given array
  • Ans. 

    Reverse the given array of strings

    • Use the reverse() method to reverse the array in place

    • Alternatively, you can use a for loop to iterate through the array and build a new reversed array

  • Answered by AI
Round 2 - Technical 

(1 Question)

  • Q1. Call api and print data in using react
  • Ans. 

    To call an API and print data in React, use fetch or axios to make the API call and then render the data in the component.

    • Use fetch or axios to make the API call in React component

    • Store the API response data in state using useState hook

    • Render the data in the component using JSX

  • Answered by AI

Skills evaluated in this interview

Interview experience
4
Good
Difficulty level
-
Process Duration
-
Result
-
Round 1 - Resume Shortlist 
Pro Tip by AmbitionBox:
Double-check your resume for any spelling mistakes. The recruiter may consider spelling mistakes as careless behavior or poor communication skills.
View all Resume tips
Round 2 - Technical 

(3 Questions)

  • Q1. How to handle state in functional components.
  • Ans. 

    State in functional components can be managed using the useState hook in React.

    • Use the useState hook to declare state variables in functional components.

    • useState returns an array with the current state value and a function to update that value.

    • Example: const [count, setCount] = useState(0);

    • State variables should be immutable, so always use the setter function to update them.

  • Answered by AI
  • Q2. What is event loop in javascript.
  • Ans. 

    Event loop in JavaScript is responsible for handling asynchronous operations by executing callback functions in a non-blocking way.

    • Event loop is a mechanism that allows JavaScript to perform non-blocking operations.

    • It continuously checks the call stack and the callback queue to see if there are any functions that need to be executed.

    • If the call stack is empty, it takes the first function from the callback queue and pus...

  • Answered by AI
  • Q3. What is hosting in Javascript
  • Ans. 

    Hosting in JavaScript refers to the process of declaring a variable or function before it is used in the code.

    • Hosting allows you to use variables and functions before they are declared in the code.

    • Variables are hoisted to the top of their scope, while functions are fully hoisted.

    • Example: console.log(myVar); var myVar = 10; This will not throw an error because 'myVar' is hoisted to the top of the scope.

  • Answered by AI

Skills evaluated in this interview

Contribute & help others!
anonymous
You can choose to be anonymous

iEnergizer Interview FAQs

How many rounds are there in iEnergizer Front end Developer interview?
iEnergizer interview process usually has 3 rounds. The most common rounds in the iEnergizer interview process are Coding Test, Technical and One-on-one Round.
What are the top questions asked in iEnergizer Front end Developer interview?

Some of the top questions asked at the iEnergizer Front end Developer interview -

  1. what is virtual dom in react and what makes it faste...read more
  2. it was HR ro...read more

Recently Viewed

INTERVIEWS

iEnergizer

No Interviews

INTERVIEWS

iEnergizer

No Interviews

DESIGNATION

JOBS

Glan Management Consultancy

No Jobs

INTERVIEWS

Company Interviews

No Interviews

SALARIES

Concentrix Corporation

REVIEWS

Flipkart

No Reviews

SALARIES

Omega Healthcare

SALARIES

HCLTech

INTERVIEWS

iEnergizer

No Interviews

Tell us how to improve this page.

iEnergizer Front end Developer Interview Process

based on 1 interview

Interview experience

4
  
Good
View more
Join iEnergizer Unlocking Potential, Unleashing Performance

iEnergizer Front end Developer Reviews and Ratings

based on 1 review

5.0/5

Rating in categories

5.0

Skill development

5.0

Work-life balance

5.0

Salary

5.0

Job security

5.0

Company culture

5.0

Promotions

5.0

Work satisfaction

Explore 1 Review and Rating
Customer Service Executive
2.3k salaries
unlock blur

₹0 L/yr - ₹0 L/yr

Senior Executive
1.8k salaries
unlock blur

₹0 L/yr - ₹0 L/yr

Customer Care Executive
1.5k salaries
unlock blur

₹0 L/yr - ₹0 L/yr

Senior Customer Service Executive
1.2k salaries
unlock blur

₹0 L/yr - ₹0 L/yr

Customer Support Executive
1.1k salaries
unlock blur

₹0 L/yr - ₹0 L/yr

Explore more salaries
Compare iEnergizer with

Genpact

3.8
Compare

Wipro

3.7
Compare

TCS

3.7
Compare

Infosys

3.6
Compare
Did you find this page helpful?
Yes No
write
Share an Interview