If you are preparing for a Javascript interview, then you have reached the right place.
Computer Science Engineering is a broad field of study that deals with the Javascript.It is a fast-growing field that has many opportunities for career growth. A Javascript interview is a type of interview that is designed to assess a candidate's knowledge of Computer Science Engineering . The purpose of the interview is to evaluate the candidate's knowledge and deep understanding of subject.
The interview may also assess the candidate's communication skills, such as the ability to present complex information in a clear and concise manner.
The Interview is typically conducted by a hiring manager or recruiter who has experience in the field. The interviewer will typically ask a series of questions about the candidate's background and experience. The interviewer will also ask about the candidate's strengths and weaknesses.
This list of interview questions in Javascript includes basic-level, advanced-level, and program-based interview questions.
Here are the commonly asked question list of Javascript (Computer Science Engineering) interview questions and answers that you must prepare for fresher as well as experienced candidates to get your dream job.
JavaScript (js) is a light-weight object-oriented programming language which is used by several websites for scripting the webpages. It was introduced in the year 1995 for adding programs to the webpages in the Netscape Navigator browser. In addition to web browsers, databases such as CouchDB and MongoDB uses JavaScript as their scripting and query language.
>Features of JavaScript
There are the following features of JavaScript:
JavaScript provides different data types to hold different types of values. There are two types of data types in JavaScript.
There are five types of primitive data types in JavaScript. They are
Non-primitive data types in JavaScript. They are
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:
myGlobalVarIs= "This is a Global Varaible ”;
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.
Timers are operated within a single thread, and thus events might queue up, waiting to be executed.
==” checks only for equality in value, whereas “===” is a stricter equality test and returns false if either the value or the type of the two variables are different.
The NULL value is used to represent no value or no object. It implies no object or null string, no valid boolean value, no number, and no array object.
Undeclared variables are those that do not exist in a program and are not declared. If the program tries to read the value of an undeclared variable, then a runtime error is encountered.
Undefined variables are those that are declared in the program but have not been given any value. If the program tries to read the value of an undefined variable, an undefined value is returned.
Cookies are the small test files stored in a computer, and they get created when the user visits the websites to store information that they need.
A cookie is a piece of data that is stored on your computer to be accessed by your browser. If you saved your user ID and password so that you do not have to type it each and every time you try to login? If yes, then you are using cookies.
Cookies are saved as key/value pairs.
Javascript Set Cookie : You can create cookies using document. cookie property like this. For example
document.cookie = "cookiename=cookievalue; expires= Thu, 21 Aug 2014 20:00:00 UTC"