Javascript, jQuery, HTML and CSS Inteview Questions Frontend Developer Interview

First Edition

Er.Vaibahv Singh Chuahan

NOTION PRESS

NOTION PRESS India. Singapore. Malaysia. ISBN xxx-x-xxxxx-xx-x This book has been published with all reasonable efforts taken to make the material error-free after the consent of the author. No part of this book shall be used, reproduced in any manner whatsoever without written permission from the author, except in the case of brief quotations embodied in critical articles and reviews. The Author of this book is solely responsible and liable for its content including but not limited to the views, representations, descriptions, statements, information, opinions and references [“Content”]. The Content of this book shall not constitute or be construed or deemed to reflect the opinion or expression of the Publisher or Editor. Neither the Publisher nor Editor endorse or approve the Content of this book or guarantee the reliability, accuracy or completeness of the Content published herein and do not make any representations or warranties of any kind, express or implied, including but not limited to the implied warranties of merchantability, fitness for a particular purpose. The Publisher and Editor shall not be liable whatsoever for any errors, omissions, whether such errors or omissions result from negligence, accident, or any other cause or claims for loss or damages of any kind, including without limitation, indirect or consequential loss or damage arising out of use, inability to use, or about the reliability, accuracy or sufficiency of the information contained in this book.

Copyright © 2021 by Er.Vaibhav singh chauhan All rights reserved. No part of this book may be reproduced in any form or by an electronic or mechanical means, including information storage and retrieval systems, without permission in writing from the author, except by a reviewer who may quote brief passages in a review.

Er.Vaibahv Singh Chuahan

Dedicating this book to the Universe within us.

व तु महाकाय सूयकोिट सम भ। िनिव ं कु मे दे व सवकायषु सवदा॥

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Contents Preface..................................................................................................................................................... vii About Author............................................................................................................................................ ix General Questions .................................................................................................................................... xi JavaScript................................................................................................................................................... 1 jQuery ...................................................................................................................................................... 99 HTML ..................................................................................................................................................... 116 CSS ......................................................................................................................................................... 148 Bibliography .......................................................................................................................................... 171

Preface This book covers Interview questions from the majour topics that are asked in interview for a Frontend Developer. Currenly it covers HTML, CSS, JavaScript and jQuery. I will try to further more in upcoming editions of this book. This book has questions for both freshers and experienced candidates.I have added almost all questions that I have came across in my carrier. I have faced many interviews myself so I know the concerns of candidate on the contrary I have also taken many interviews which makes me familier with the other side too. Although I have tried to cover many questions and answered them in berief.You are advised to have further knowledge by digging deep in case you are not familer with a concept as the explanation is short for many questions. For few most important sorts of questions I have given a long descrption which might help candidate further.In case of you find any typo or error in the book or if you want to contact me in case of any queries you can mail me directly on [email protected]

All the best for your Interview Preparations Er. Vaibhav Singh Chauhan 14th May 2021

About Author Er.Vaibhav Singh Chauhan is a software consultant and has a wide experience working in corporate environment.He has served as Project Leader and Team Lead in some reputed organizations working for Swidish,US,UK,Japanse and Indian clients.

Website : https://vaibonline.com Email

: [email protected]

General Questions 1. Introduce Yourself? Freshers: I have persued my Engineering from Lakshmi Nrayan college of Technology, Bhopal which is prestigious institiute in central India. My specilization was Computer Science Engineering.I have knowledge of frontend design and programming with HTML and CSS concepts and some knowledge with javaScript and jQuery.i have made my Majour project using same technology with the name “Project name”. Experienced: I have a total Expreince of 8 years and overall Experience eof 7 Years in Frontend UI development.In my carrier i have designed frontend using HTML,CSS and some responsive frameworks like bootstarp .I have experience with jQuery and JavaScript.Additionally i have experience with ..............I also got chance to work as Team Lead/Tech lead in last couple of organizations. Talking about the project domain/types, I have worked with Egov organizations, E-commerce, product based, Service based, Heath Domain, Finace Domain projects. Note: Customize a bit as per Job Description (JD). 2. Explain your Major Project/ Currect Project for Experienced Candidates? Explain the project artchitecture, team size, your role and responsibilities in the project. 3. What is the reason for job change? You need to find the best reason as you already know it deep down.Some reasons can beLate salary payment, Appraisal concerns, unhappy with the technology you are currently working with and such reasons. 4. What is the reason for gape/Break in Education/Experience?

Javascript, jQuery, HTML and CSS Inteview Questions

You already know the real reason behind.Explain the family situations or other reasons that occurred during that time. And at the end don’t forget to mension that everything is well now and you are ready and very enthusiastic for this job. 5. Why so many frequent switches? In case you have switched organizations frequently, be prepaired for this question. You need to give best reasons to support your argument.There may be contractual jobs, explain them those contacts or there might be a company which has shutted down its operation. So you need to write down a good reason on paper for every switch.

6.How will be rate yourself on scale of 1-5 in jQuery? Interviewer may as this question before starting your technical interview.Be carefull while rating yourself. Don’t go for 5 unless youy are a genious in that particular technology.

7.Where would you like to see yourself in next 5 years ? Generally interviewer asks this question at the very end of interview and mostly to freshers.By that time you will get a bit familier to interviewer and you will kind of know him/her. Get your answer accordingly. Generally a Team Lead / Tech Lead is fine to say. You can also go for higler posts like project manager or furher more but be casious in case your interviewer is too judgee type . 8. Explain any one situation in which you did extraordinary in some project work? Generally asked to experienced candidates.Be ready with a case where you have used some higher concepts and produced some good results which were very unusual. So better be a short story teller for such questions. It’s just a question to get an idea about you. Be confident and make some notes about it.

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JavaScript 1. What is JavaScript? JavaScript is a client-side and server-side scripting language inserted into HTML pages and is understood by web browsers. JavaScript is also an Objectbased Programming language 2. Enumerate the differences between Java and JavaScript? Java is a complete programming language. In contrast, JavaScript is a coded program that can be introduced to HTML pages. These two languages are not at all inter-dependent and are designed for different intent. Java is an objectoriented programming (OOPS) or structured programming languages like C++ or C, whereas JavaScript is a client-side scripting language. 3. What are JavaScript > 2

Er.Vaibhav Singh Chauhan

function addNode () { var newP = document. createElement("p"); var textNode = document.createTextNode(" This is a new text node"); newP.appendChild(textNode); document.getElementById("firstP").appendChild(newP); }

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11. What are global variables? How are these variable declared? Global variables are available throughout the length of the code so that it has no scope. The var keyword is used to declare a local variable or object. If the var keyword is omitted, a global variable is declared. Example: // Declare a global: globalVariable = "Test"; The problems faced by using global variables are the clash of variable names of local and global scope. Also, it is difficult to debug and test the code that relies on global variables. 12. What is a prompt box? A prompt box is a box that allows the user to enter input by providing a text box. A label and box will be provided to enter the text or number. 13. What is 'this' keyword in JavaScript? 'This' keyword refers to the object from where it was called. 14. What is the working of timers in JavaScript? Timers are used to execute a piece of code at a set time or repeat the code in a given interval. This is done by using the functions setTimeout, setInterval, and clearInterval. The setTimeout(function, delay) function is used to start a timer that calls a particular function after the mentioned delay. The setInterval(function, delay) function repeatedly executes the given function in the mentioned delay and only halts when canceled. The clearInterval(id) function instructs the timer to stop. 3