It is different from Java language. Inner functions in JavaScript have access to all of the variables defined in the outer function. To test the code, the debugger must be enabled for the browser. Here’s a typical example of a named function. It’s better to store the JavaScript Codes, CSS, and HTML as separate External ‘js’ files. Let’s take a sample code. The following example illustrates the usage: window.document.body.style.cursor = “wait”; No, Java and JavaScript are the both are different languages. We assign the object from “this”, to another(non-special) variable, “self”. Yes, as a result of it doesn’t require web server’s support for execution. Let’s take an example of creating an object using the object constructor technique. Secondly, Type converting equality (==), automatically converts the variable to value irrespective of the data type. JavaScript is an interpreted programming language. If used at the beginning of the js file, its scope is global. A form object is used to take user data as input for processing. When we check the data type of ‘true’ or ‘false’ using typeof operator, it returns a boolean value. Taking an example, “2” will not be equal to 2  i.e. ... Mar 29, 2019 at 5:36 am GMT Most of the questions are outdated and no longer asked in Interview. This JavaScript interview questions blog will provide you an in-depth knowledge about JavaScript and prepare you for the interviews in 2020. A cookie is a piece of data which is sent from a website (that owns the requested web page) and gets stored locally by the browser at the user end. JavaScript Code has better performance. Answer: While using the ‘JavaScript Hoisting’ method, when an interpreter runs the code, all the variables are hoisted to the top of the original /current scope. Let’s see a sample example: document.getElementById(‘mylocation’).innerHTML=”

This is heading using JavaScript

”; The innerText property is empployed to write the simple text using JavaScript dynamically. Please refer to previous Q #11, as explained there, the interpreter will take all the variables declared except initialization to the top. The navigator.appVersion string can be used to detect the operating system on the client machine. In Javascript close() method is used to close the current window. This is to ensure that the correct values are used when a member’s context changes. Here’s the same example created as an anonymous function. Answer: Yes, JavaScript is a case sensitive language. Here the variable ‘num’ is used before declaring it. Create a single global variable that holds all your other variables. Answer:  JavaScript is called as a loosely typed or a dynamic language because JavaScript variables are not directly associated with any value type and any variable can be assigned and re-assigned values of all types: Answer: The value null represents the intentional absence of any object value. The push() method adds one or more elements to the end of an array and returns the new length of the array. If you are preparing for an interview, here are the most frequently asked JS Interview Questions and answers for your reference. The variable declared with ‘var’ be hoisted, The variable declared with ‘let’ be hoisted, It is known as ‘Type Converting Operator’, It is known as ‘Strict Equality Operator’, using ‘let’ we can change the value of variable any number of times, using ‘const’, after the first assignment of the value we cannot redefine the value again. If we call the constructor with two or more arguments, it declares an array with array elements also initialized. When you inherit from a delegate prototype, the new object gets a reference to the prototype. It doesn’t need to define a class for creating an object instead creates it directly. A name-value pair containing the actual data, An expiry date after which the cookie is no longer valid, The domain and path of the server it should be sent to. JavaScript variable names should not start with a numeral (0-9). Answer: Both ‘==’ and ‘===’ are comparison operators. About us | Contact us | Advertise | Testing Services All articles are copyrighted and can not be reproduced without permission. Here is a code example describing closure by adding a function inside another function. Q #25) What is the difference between ‘function declaration’ and ‘function expression’? Cursor can be set  in JavaScript by using “cursor” property. And there is a high probability that you might face similar types of questions during interviews. Answer: Anonymous functions are functions without having any name and won’t do anything on their own. BigInt is created by appending n to the end of an integer. And with the inception of new technologies like AngularJS/Node.js, it shall expand further. JavaScript supports three Primary, two Composite and two Special data types. –’ HTML tag. ’Var’ keyword has function scope. This method takes a single parameter, the character you want to separate the string at, and returns the substrings between the separator as items in an array. Answer: A closure is an inner function. The outer function is calling the inner function add(). This function has no name. In Asynchronous programming, the engine runs in an event loop. A boolean variable can be created using the Boolean() function. In JavaScript, a function can create an object. There are three methods of history object. We need a way to get a reference to the object, that is available inside the nested function. Now you introduce the settimeout() method and wrap the same set of code in it. A closure is a JavaScript function defined inside another function. Cookies are needed because HTTP protocol which arranges for the transfer of web pages to your browser, is stateless. However, “this” variable is an exception. Q #30) Can you give an example showing JavaScript Hoisting? A Symbol value represents a unique identifier. It is important in JavaScript because it’s suitable for user interface code and beneficial for maintaining the performance on the server. To read a Cookie, we have to access the value of the object. Q #22) What is the difference between ‘let’ and ‘const’? Netscape provided the JavaScript language. I am ‘Jerry’. Please follow the below example. true or false. In JavaScript, variable declarations are the first piece of code that executes irrespective of their location.