Mindtree React Js and Javascript interview | 🎉 Selected | ReactJs Interview question answers

[@DevAditya]

Telegram group - t.me/Reactjs_Interview Please don't judge and comments on my answers. this is just the interview experience and If you know the right answers please comment below which can also help others. Instagram - instagram.com/dev.roshan_ twitter - twitter.com/dev_roshann

[@anandwadsinge3913]

- What is lifecycle method in react ? - How will you convert class based to function based component in react? - How do you manage state in component? - Redux middleware ? => Saga and Thunk - Why do we need middleware in redux implementation? => to capture error log etc. - Why do we need typescript instead of javascript? => - Explain use case with typescript? - Do you know server side rendering in react? - How to style a component in react? => used .css and .style component directly - Have you used any library in react? which one please explain? - In materialUI what does makeStyle function do? - Can we use multiple className in same object for materialUI? Ex. in gridUI can we use? - What is your testing strategy? => we use unit testing (JEST) - I am creating a application and it should support two language - English & Hindi - so you are developing there application in react - so what will be your approach? - Have you worked in CMS (Connect Management System)? => Wordpress - CODE - Team Member size - How do you manage project any tool you use? => gitlab - Are you following any agile method in project - Do you have any experience in Devops?

[@DevAditya]

Thanks

[@olabisiajoseh9141]

Thank you

[@fevicoI]

The question standard is decent. It’s not only about easy questions, interviewers check your depth of knowledge, they may expect you to explain in depth about JavaScript stack, and async non blocking operations how it works, etc.

[@galax5130]

for question 1:34 it will print 1 because setTimeout function goes into callback and takes 1 second to be executed in that mean time x will be declared in function function x() stack frame and it will be accessible for callback function of setTimeout

[@MultiReview]

It will possible because of hosting

[@bibhasash7371]

2nd question answer will be 1 because after the callback function of the setTimeout come inside the callstack the i nis already declared and initialized so it will print 1

[@Mbl43]

- [00:00](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 📝 Coding Logic and Approach - Understanding the order of execution of asynchronous JavaScript code. - Implementing recursion to traverse and extract data from nested objects. - [04:11](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🧠 ReactJS Lifecycle Methods - Explaining the three phases of ReactJS lifecycle: mounting, updating, and unmounting. - Converting class-based components to functional components using useEffect for lifecycle methods. - [07:12](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🖥️ Managing State in React - Using the useState hook to manage state in functional components. - Describing how to manage state across multiple components using props drilling and Redux. - [10:08](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 📦 State Management with Redux - Contrasting Redux and Context API for state management in React. - Explaining the concepts of actions, reducers, and dispatch in Redux. - [13:12](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🔄 Middleware in Redux - Defining middleware in Redux and its purpose in intercepting actions. - Mentioning Redux Saga and Redux Thunk as examples of middleware. - [15:22](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🔤 Advantages of TypeScript in React - Discussing the benefits of TypeScript for error reduction and type safety in React development. - Providing an example of using TypeScript interfaces for component parameters. - [17:16](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🌐 Server-Side Rendering with Next.js - Sharing experiences with Next.js for server-side rendering and API handling. - Highlighting advantages like simplified routing and built-in SSR support. - [18:19](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🎨 Styling React Components - Mentioning usage of CSS files, styled-components, Sass, Bootstrap, and Material UI for styling. - Explaining the role of the makeStyles function in Material UI. - [19:36](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) ✔️ Unit Testing Strategy - Describing the use of Jest and Enzyme for unit testing React components. - Sharing a preference for testing all components and utilizing snapshots. - [20:48](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🌍 Multi-Language Support in React - Discussing globalizing components using libraries for multi-language support. - Admitting lack of familiarity but mentioning previous usage in a project. - [21:30](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🛠️ Interaction with CMS (WordPress) - Sharing experience developing a React plugin for WordPress. - Expressing the need to review documentation for data interaction. - [32:49](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 🔄 Project Management and Version Control - Describing the use of GitLab for task assignment, branch creation, and merge requests. - Adhering to agile methodologies for project management. - [33:05](kzbin.info/www/bejne/iJLTlJSdi9l1Y5I) 💼 Future Opportunities and Learning - Inquiring about potential project assignments and technology stacks. - Asking about the possibility of working on both front-end and back-end tasks.

[@soumyajitdey5720]

The problem with async await was that you didn't put await before res.json() but kudos to you that you remained calm and changed it to .then() chaining and got it done!

[@DevAditya]

😊 thank you

[@barreddimensions7155]

wow...those were actually an easy questions. I am a MERN developer with two years of gap after graduation and yes, 0 working experience or company exposure 😂. I thought company like infosys have tough interviews. Thank you, I think i gained a litttle confidence. Thanks for sharing...

[@DevAditya]

It depends on the Interviewer

[@crystalclear178]

Do We need fake experience after gap?

[@crystalclear178]

Please give me idea i also have 4years of gap

[@programmerarnab9046]

Truly.. this interview was like asking a newbie.. I thought thier interviews are very hard . Btw I can also point out that a lot of time people do not know how to explain properly.. but these questions are like normal chatting then an interview 😜 we can have debates how hours on these...

[@amolchopade7649]

@@crystalclear178 If you apply as fresher then it will difficult to get call for interview. if you show fake experience then interview gets more difficult.

[@aniketbisht763]

Hi bro!, At 2:00 it will print the value of i since set time out is an asynchronous function it will go to the callback queue but In the meantime i variable will be defined

[@g8dboyplays790]

Yes, you are correct!

[@shilashm5691]

Difference between framework and library? Answer: who calls who!? if we call the external code, then it is library. If our code is called by another code then it is framework. It is the concept of Inversion of control!

[@DevAditya]

Thanks for explaining

[@shilashm5691]

@@DevAdityaPleasure bro, How much they offered?

[@aniketbisht763]

I thought library is what we can use functions but framework is like the base project in which we can add our functionalities, am I wrong?

[@kshitijvengurlekar1192]

You have to add custom middleware like Redux thunk or saga to do things like fetching data from API. And then you will be able to return a async function from the action which will return a pure JSON object once the API response is received. The interviewer was trying hard to bring you to that point.

[@DevAditya]

Yeah, that time got confused actually. BTW thanks for explaining

[@lokeshnandanpandey5681]

@@DevAditya can you tell me your insta I'd

[@DevAditya]

@@lokeshnandanpandey5681 Instagram.com/dev.roshan_

[@rootnode6571]

@Kshitij Vengurlekar Not necessarily, you can easily achieve this using a simple useEffect, or create a custom hook to fetch API data. :)

[@kshitijvengurlekar1192]

@@rootnode6571 I want to dispatch an action, And I expect that Action to make an API call , fetch data and update the Redux store. Can you link some article that shows how can useEffect or any other custom hook be used here?

[@SaudagarDalve]

Demonstrated good knowledge with in-depth responses.

[@cubastic_rahul]

Superb bro....!!!

[@kudaykumar1261]

Thank you so much for sharing this interview... It's really helpful. The interview really good

[@swaniketchowdhury]

29:30 I think you missed the async keyword. If you are using .then() & .catch(), you don't need to use an async function.

[@DevAditya]

Right, Actually before this I was implementing async-await & later then-catch that's why forget to remove it

[@swaniketchowdhury]

@@seenu9633 syntactically i think it will not give any errors, but there is no need.

[@pathanaamir38]

thank you for sharing your experience of intervew.

[@amygoru8229]

Thank you for sharing Sir

[@KrishnaDasPC]

The menu structure we are using in our app. recursion is what used.

[@printmusic5m50]

Thank you so much for sharing.....

[@jayjani740]

@03:36 Why recursion? I think you can do it via deep copy. JSON.parse(JSON.stringify(data))

[@saifullasoudagar7404]

we can do like this also right data.map(item, 'name')

[@saifullasoudagar7404]

using lodash method

[@pradyumnagarg]

I think the interviewers intension was to demonstrate a scenario where you have a nested object upto nth level here value of n is unknown or variable. And we want to react the leaf or the last level of object to extract the data, that's why recursion is the most suitable solution here.

[@shubhamrawat2652]

We can use reduce here

[@Manjunath-vv3fg]

Thanks brother, this will help me a lot

[@kumarswamy2979]

Hi Roshan, These videos really very helpful. Thanks for this initiative 👍👏🙂

[@DevAditya]

Glad to know it helps 🙂 Keep supporting

[@tarangsachdev4225]

function myFunction(){ var oa2=2; setTimeout(function(){ console.log(oa); console.log(oa2); },1000) var oa=1; } myFunction() it will not print undefined and 2 instead it will print 1 and 2

[@DevAditya]

Exactly 😅

[@guru6031]

Yes it is clousers question..

[@tarangsachdev4225]

to understand it clearly, you need to learn how execution context work (Creation Phase and Execution Phase)

[@devarora3770]

is it due to hoisting or due to closure .?

[@souravkumar-hl2ot]

@@devarora3770 it's hoisting

[@abhyudayghatale3527]

Thanks for sharing!!

[@AashishKumar-vb3qb]

Thanks , Its helpfull 😃😃

[@DevAditya]

Glad to know that 😊

[@shilashm5691]

Prop drilling can be solved using context api and component composition

[@CloudMadeEasy]

Set time out will take time this is not true.. you need to explain how set time out register in Colstack

[@SONUKASHYAP]

Can you tell me what was package for this React interview. And You are Freshers or exp.. because questions is like freshers level.

[@chayanjana20]

May be you get 1 cr...congratulations.. 😄😄😄

[@joeljohnson1478]

I am a react developer in Infosys and I'm getting a package of 6.25LPA

[@abhayshrivastava2075]

@@joeljohnson1478 experience?

[@toffcodes4337]

What's your experience?

[@aimanhussain2818]

@@joeljohnson1478 how to join Infosys..plz suggest

[@shubhamambhore5707]

Thanks for sharing...too helpful 🎉✌🏻

[@DevAditya]

Glad it helps 🙂 Keep supporting

[@paieu]

its been 3 months into web dev i understood all of this question and know the answer!

[@DevAditya]

Great!

[@Lens_n_love]

1:56 he wanted to know about hoisting

[@dubey_ji]

Great bhai 💪👌

[@DevAditya]

Thank you

[@divyanshugarg2831]

bro passing index as key in a map loop is the worst thing you can do in react learnt it the hard way time stamp 30:00

[@RandomGuy34-j1u]

why ?? what is even wrong in it ??

[@kapilkumar2020]

Thanks for the intiative Really helpful

[@DevAditya]

Glad to know it helps 🙂

[@shubhamraikwar4725]

I think, the answer for this code should be 1 after 1sec and not 0. function x() { setTimeout(function() { console.log(i); }, 1000); var i = 1; } x();

[@coder-webdev5907]

Somebody help me in this problem Please write solution in javascript Write a function called do_allocation(number_of_people, number_of_buses) The function should return a list of number of people who can get into the next bus that comes in based on the following logic: Each bus’s capacity is the sum of the capacities of the previous two buses. Once all the people get in, then the buses can continue, but will have 0 people inside it. This is the case when the number of people are less and there are more buses. So after all the people are already boarded, then the remaining buses will have 0 people boarding. The output of the function is an array/list with the same length as number_of_buses. The total of this output array/list should be less than or equal to the number_of_people. The first bus’ capacity can be set to 1 by default. E.g. Def do_allocation(number_of_people, number_of_buses): …. Your code…. Return array[number of people got into first bus, number of people got into second bus, …. , number of people who got into last bus]

[@alenevins1087]

Was the answer to second ques correct?? I think it will print 1 and not undefined as we used var

[@vivekanandareddymaddela]

I feel Json.parse(Json.Stringify(obj)) would do work

[@aayushrawat6937]

yes due to Hoisting

[@shubhamrawat2652]

Yes due to hoisting

[@ritabratagoswami7724]

I ran this program i found not only by VAR but also by let and const the hoisting is possible. And printing 1.👍

[@WeakCoder]

@1:33 just wanted to know if your answer was correct ? Or does JS hoisting take place here ?

[@jiteshsharma8258]

The answer will be 1 because by the time log in timeOut will log the value of i will be 1

[@nagarajuguntruttu7145]

Nice video , can I know the package for this .!

[@anusuyadevithalavaisamy1425]

Thanks for sharing.. it is very helpful for me :)

[@DevAditya]

Glad it helps 😊 Keep supporting!

[@codinggurujii]

Can anyone explain exactly how second structure problem will solve?

[@sandeeppatil5905]

can you please make the separate list of questions and answers and provide the link

[@DevAditya]

Sure, in upcoming videos 🤗

[@sandeeppatil5905]

Thank you, ​@@DevAditya

[@kumarmanish9046]

4:45 you said componentDidmount for BOTH, component loads and also for component updation. Is that right answer?

[@DevAditya]

When loads ComponentDidMount When update ComponentDidUpdate

[@techie-alien4712]

Hey @Dev. Roshan ! Its amazing!! This is for experienced level, can you give pointers to level of difficulty for react.js questions, if it was for a current final year student with reference to this interview. Your guidance would help me a lot. Thanks!

[@DevAditya]

Thank you 😊 & It was for an experienced candidate but you can consider these questions, it'll be beneficial for you.

[@rakeshpatel1975]

@Roshan, How much experience do you have?

[@kumarmanish9046]

OMG who uses a varibale with Capital letter!!!!!!!!! UseState? or useState? 9:00

[@DevAditya]

I'll suggest not to consider my answers do your own research, It's just an Interview experience. BTW I was not running the code, just wanted to explain.

[@vivekverma-gg6be]

@@DevAditya Nice explanation overall. Just for closure question variable defined below the setTimeout will give the same result as 1.

[@DevAditya]

@@vivekverma-gg6be Thank you

[@souvikbhattacharyya9952]

bro was not there any Dsa round ? and aptitude round. i am a fresher that's i want to know more

[@DevAditya]

It depends on the interviewer.

[@AnuMessi10]

mostly when you apply for front-end/back-end/full stack roles, the primary questions are based on the tech stack (JS and react in this case), DSA is usually optional upto the interviewer

[@nirmalrathore5913]

What is happening for me interview not get cleared but I am handling 3 project 2 as a shadow Dev.

[@DevAditya]

They expect theoretical explanation in better way.

[@sourabhjyotidasusedlessguy6107]

My bro seleced everywhere but goes nowhere.

[@akshayyadav7629]

Bro well can you also tell that what are the questions for the freshers ?

[@DevAditya]

You can consider the same

[@Hindutvavadi2]

This interview for entry level??

[@niteshbisht31]

Can u make an explanation video for the question that was asked at 03:00 min?

[@DevAditya]

Sure, will try to cover these questions on a separate video

[@Jayscoffee]

what was the salary offered?

[@jenasusil6]

Why you use middlware ? We use it for asynchronus operation. Redux thunk usecase? redux thunk is a midleware, as i mentioned middleware is use for async operation. insted of returning a action ,it will return a function. this function is a pure function. How many years of experiance you have ? Please go through the basics of everything. it seems like you have prepared randomly with some video tutorial. not clear about anything. while you use async await you should not use .then and .catch. you should use try catch .once you mark a function async this function will return a promice so no need to use .then

[@DevAditya]

Thanks for the suggestion

[@vimalsankar2503]

how did you record this interview? any tool?

[@DevAditya]

cmd+shift+5

[@websiteaudit]

Brother please add the filter code .on fetching .

[@websiteaudit]

Waiting for reply please write the both methods

[@itsMe-oq5em]

How much package u got brother?

[@satishmaurya2089]

thanks buddy

[@notyournormaldev1419]

All questions were not answered clearly...how you are selected..half sorted answers.

[@sivanagajayavardhanchintam9881]

Bro, could you please show me way to learn React ..I'm a beginner Mern developer... any ways about React,node js and MongoDB will help me a lot.

[@likhithsagar6847]

hey there, you can checkout TheNetNinja tutorials on KZbin. It got complete playlists for all ur requirements : )

[@rohitsakhare2247]

I was also selected, but the offer letter has not come yet, I had a tech round,tech manager round ,after that they mailed me the documentation,i submited documentation but still waiting for offer letter , i gave interview on 9 Apr

[@DevAditya]

All the best.

[@rohitsakhare2247]

@@DevAditya any idea about ? Why they are taking time for release offer letter

[@SagarKumar-db2xy]

@@rohitsakhare2247 bhai kanha apply kiya tha

[@sanjibmajhi85]

@@rohitsakhare2247 for my case I've given my first technical round on 19th march On 20th March I've got a mail to upload documents On 25th March I've given managerial round On 28th March I've HR called me for salary negotiation, and they told me to wait 2 weeks On 8th April I've got my offer.

[@vishaltiwari3900]

@@sanjibmajhi85 hello my interview was on 23rd APR 2022 on same day at night got documents upload mail but no update after that.

[@sachin__ak]

The question level was very basic.

[@jason5767]

Is it for freshers? or experienced 1-3 years interview?

[@karthikbalaji383]

what is the package?

[@akshayyadav7629]

I think this interview is for experience candidate right. How much experience is required for the interview ?

[@DevAditya]

It was for 2+ exp

[@poulamimukherjee9193]

Hey, what was your answer when he asked you if you have knowledge about DevOps?? Was not able to catch it properly in the video. TIA😊

[@DevAditya]

I'll suggest not to consider my answers.

[@poulamimukherjee9193]

@@DevAditya But I think the interviewer was impressed by your answer and ddnt press the question any further. You fared well😊

[@DevAditya]

@@poulamimukherjee9193 My answer on it was "No but I'm curious to learn it"

[@DevAditya]

@@poulamimukherjee9193 thank you 😊

[@mohsinpathan5873]

Thanks for sharing..

[@DevAditya]

Keep supporting 😊

[@gullukumar4497]

Paisa kitna (range) de rha h bhai?

[@bryce8595]

did you get the job? i go for an interview in may little nervous. Also the first question I is still gonna be one because its initialized in the outer function, if it was initialized in the inner function x wouldn't know what it is

[@DevAditya]

Exactly, I made this mistake. BTW received postive feedback from them

[@DevAditya]

All the best

[@ps_abhishek]

I think the interviewer may be a Malayaali😁. That slang..🧐

[@abhinavvp5936]

Felt that too

[@bhagyalakshmi1053]

Letter never confirm letter scene

[@arunsoni5471]

Nice..

[@DevAditya]

Thanks

[@hemanthreddy5899]

Package?

[@shivangchheda6311]

how did he land this interview? cause in mine there nothing like this asked also I am freshers is it for someone with experience

[@DevAditya]

Yup Exp

[@shivangchheda6311]

@@DevAditya what if you have similar knowledge and is it possible to apply for same ?

[@abhishekmaldikar9704]

Was this a fresher or experienced interview

[@carryminatifans5896]

Wow...

[@vancedtube96]

is it for fresher job? or experienced one? how many years.

[@DevAditya]

2+ exp

[@surendravaddi9054]

how many years of experience ?

[@DevAditya]

3+

[@compeng..1510]

@@DevAditya hii bro

[@compeng..1510]

@@DevAditya i also want to crack mnc company but the problem is i have signed a bond with my startup company.

[@DevAditya]

@@compeng..1510 you must have to complete it then.

[@nikhilarya7712]

@@DevAditya bro koi compulsory hota hai bond pura krna mtlb koi jabardasti to nhi hoti h isme?

[@gulrezeqbal3048]

How much experienced?

[@ganeshmandapati4799]

How much percentage hike you got??

[@DevAditya]

Can't disclose here, Insta or telegram

[@ganeshmandapati4799]

@@DevAditya check your Instagram

[@ganeshmandapati4799]

@@DevAditya reply on Instagram bro

[@DevAditya]

@@ganeshmandapati4799 ok

[@KarthikJsuvarna]

Was there any DSA

[@DevAditya]

Yes Depends on the interviewer

[@KarthikJsuvarna]

@@DevAditya what really? That's great

[@Ak-.-47]

Is this for freshers or experienced.

[@DevAditya]

Exp

[@inspiringstories143]

that person selected yes or not

[@DevAditya]

🎉 Selected

[@6713G]

Whats you experience bro..!!?

[@satigamingofficial9738]

How many years of experience you mantion in your resume for this interview..

[@DevAditya]

2+

[@piltonswrangbrahma5140]

CTC?

[@malikshahid886]

Was it for a fresher or u had some prior experience?

[@DevAditya]

Exp

[@malikshahid886]

@@DevAditya Can i apply as a fresher? How to approach?

[@DevAditya]

​@@malikshahid886 Not sure about the Fresher but you can take help of Payroll companies or it would be better to connect on LinkedIn & ask for reference who's working there.

[@ManishGupta-de9qf]

For how many years of experience was this role about?

[@mrsrv7]

Based on the questions, I think this might be for a fresher

[@kamleshbachani8132]

Inverview for which level?

[@DevAditya]

Exp

[@inshafahmed8656]

function x() { setTimeout(() => { console.log(i); }, 1000); var i = 1; } x(); // This will print => 1

[@DevAditya]

Right 👍

[@thepravinbtech]

Ishiitttt visibbbbble

[@Abhinendrachauhan1993]

How many total rounds were there? Was it the first round.... and what were the other rounds, please also tell me your experience.. And congrats..

[@DevAditya]

1 Tech round only & HR exp -2+

[@DevAditya]

Thanks

[@Abhinendrachauhan1993]

@@DevAditya Thanks for the response. My interview is also going to get scheduled soon. The video was really helpful.

[@DevAditya]

@@Abhinendrachauhan1993 All the best 😊 Be prepared with ES6 features in deep also

[@Abhinendrachauhan1993]

@@DevAditya Thanks. I will look into that.

[@udayshankhar8482]

Is this a fresher interview bro??

[@DevAditya]

No, but you can consider

[@omkarshinde7466]

3 years ye hisab se bahot fattu que the 🤣🤣

[@ankitagupta3882]

How much experience did you have when you gave this interview ?

[@DevAditya]

2+ in react

[@chetanpl]

Your voice is low

[@DevAditya]

You may use the earphone bro

[@chetanpl]

@@DevAditya after use of headphone. I am replying you.

[@compeng..1510]

How much package infosys offered?

[@DevAditya]

As per the Industry Standard

[@compeng..1510]

@@DevAditya how much pls give a range

[@bhagyalakshmi1053]

Letter never coming later please plastic

[@phoneix24886]

Lodu company ka lodu questions.

[@urvilshah4724]

.eificii