|
Website Chatter >
Top Most Commonly Asked JS Interview Questions
Top Most Commonly Asked JS Interview Questions
Community Sharing
Page:
1
Vishal Devji
1 post
Dec 28, 2022
5:58 AM
|
Javascript is being used by Google and Facebook to create sophisticated, dekstop like web applications. Node.js release has made it one of the most widely used languages for creating server side software. If you don’t know what is node.js then you can plan to learn it from scratch with Nodejs training online.
Even the modern internet cannot accommodate javascript’s adaptability. It is a must to learn language for every aspirants pursuing web design courses in Delhi.
Let’s check the top questions.
Q.1 Is there any difference in the languages Java and JavaScript?
Ans. Java: Java is an object oriented programming language. It creates application that run on virtual machine. For better understanding, you can check Core Java course in Delhi.
Java-script: It is an object oriented programming scripting language and its code run on browers only.
Q.2 How would you define Javascript?
Ans. JS is a light weight, case sensitive programming language. It is used to give interactivity to webpage and it onverts static web page into dynamic web page. To understand in detail, you should join JavaScript course in Delhi.
Q3. What is callback in javascript explain with a simple example?
Ans. Everything in javascript is consider as object so function is also object. So simply Callback is a normal function of JS. If you ask for its work then it mainly passes argument to other functions for the execution at the time of the completion of the operations.
Here is an example of callback function
Q4. What is scope in javascript?
Ans. Each function in javascript has its own scope. For accessing variable name, scope is a collection of variable as well as the rules also. Only code contained within that function has access to the function’s scoped variables.
Only code contained within that function has access to the function's scoped variables. Variable name should be different inside same scope.
Q.5 What do you understand by Undefine and Null?
Ans. Null is a primitive data type. It shows a planned absence of a value. Null always accepts null value so it is not useful.
Undefined: undefine means that a variable in declared but not initialize and in this scenario value will found undefine.
Q.6 what are the rules for naming a variable?
Ans. 1. Do not use any reserved keywords for a variable name in javascript like. Boolean, break.
2. Variable name should not start with digits (0-9).
3. Variable name should start with camleCase, or with special symbol.
Q.7 Explain DOM in javascript and how to access HTML elements with the help of DOM?
Ans. In javascript, DOM is known as document object model. With the help of Dom all Html elements can be changed.
With the help of DOM attributes of Html can be changed.
With the help of Dom existing element of Html can be changed.
And there are few methods in javascript for targeting html elements.
1. getElementById()
2. getElementsByTagName()
3. getElementsByClassName()
4. querySelectorAll()
Q.8 what is the difference between local storage and session storage?
Ans. Local storage: Every HTTP request (Html, images, javascript, css and so on) does not send back to the server. This reduces the overall traffic that comes between client and server.
It will remain until manually cleared via setting or programme.
Session storage: Difference between local storage and session storage is not so much. It is just that whatever data stored in local storage has no ending time but session storage have it will erase all the data as soon the session ends.
You can also learn with PHP training institute in Delhi to understand how database and storage of websites work.
Q.9 what are escape characters in javascript?
Ans. If you want to write some special character like comma, single quote, double quote, ampersands then javascript’s escape characters makes it easy for you. Werever you want to use theses escape characters place it before that character.
Q.10 How to read cookies in javascript?
Ans. Cookies are small string of data stored directly in browser. And it’s very simple to read cookies in javascript. We can make use of the document. Cookie that keeps the cookie using the string that we just created.
So, these are some of the main questions that an interviewer can ask you. Complete your training under web development courses and focus on practical examples more as then only you can crack these types of programming interviews.
Last Edited by Vishal Devji on Dec 28, 2022 6:08 AM
|
Manoj
Guest
Jan 12, 2024
9:43 PM
|
Best office interior: Embrace the charm of industrial design for a contemporary and trendy office space.
|
Manoj Rawat
Guest
Feb 23, 2024
3:12 AM
|
Health is one of the most crucial aspects of our lives that we have to take care of. We need to make sure that our body is free of any kind of disease or sickness. We also need to make sure that we are in the best of health and that we are doing the right thing to keep ourselves healthy. Top Sexologist In Noida
|
Post a Message
|
|
|