What is this keyword in JavaScript Mcq?

What is “This” Keyword in Javascript? “This” keyword refers to an object that is executing the current piece of code. It references the object that is executing the current function. If the function being referenced is a regular function, “this” references the global object.

What is the this keyword in JavaScript?

In JavaScript, the this keyword refers to an object. Which object depends on how this is being invoked (used or called). The this keyword refers to different objects depending on how it is used: In an object method, this refers to the object. Alone, this refers to the global object.

Can we use this keyword in JavaScript?

And it is only relevant within the class. JavaScript also has this keyword. However, the this keyword in JavaScript behaves differently from other programming languages. In JavaScript, you can use the this keyword in the global and function contexts.

What is mean by this keyword in JavaScript o It refers current object o It Referes previous object o It is variable which contains value o None of the above?

this keyword in Java is a reference variable that refers to the current object of a method or a constructor. The main purpose of using this keyword in Java is to remove the confusion between class attributes and parameters that have same names.

Which type of JavaScript language is Mcq?

01. JavaScript is which type of language? Explanation: JavaScript is not a pure OOP's (object-oriented programming) oriented programming languages such as PHP, Java, or many other programming languages, although it is an object-based language.

JavaScript this Keyword

Which tag is used to write the JavaScript code Mcq?

What is the HTML tag under which one can write the JavaScript code? Explanation: If we want to write a JavaScript code under HTML tag, you will have to use the “script” tag.

What is the original name of JavaScript Mcq?

Javascript MCQs Questions

The project was originally called Mocha, then renamed to LiveScript, and finally to JavaScript when Netscape and Sun did a license agreement.

What is this keyword?

The this keyword refers to the current object in a method or constructor. The most common use of the this keyword is to eliminate the confusion between class attributes and parameters with the same name (because a class attribute is shadowed by a method or constructor parameter).

Why this keyword is undefined in JavaScript?

The this keyword of the clickMe arrow function refers to the global object, in this case the window object. So, this. position and this. color will be undefined because our window object does not know anything about the position or the color properties.

What is this keyword in node JS?

By default, this refers to a global object, which is global in the case of NodeJS and a window object in the case of a browser. When a method is called as a property of an object, then this refers to the parent object. When a function is called with the new operator, then this refers to the newly created instance.

What is this keyword in react?

In React when we use event handlers we basically give a reference of a function to that event handler and when that event occurs that function gets invoked, here's a catch, it's invoked at some point of time not immediately, and when its invoked, it's invoked as its own, there is now any components instance object ...

Is this a JavaScript operator?

JavaScript provides the following logical operators. && is known as AND operator. It checks whether two operands are non-zero or not (0, false, undefined, null or "" are considered as zero). It returns 1 if they are non-zero; otherwise, returns 0.

What is this in programming?

The keyword this is a Java language keyword that represents the current instance of the class in which it appears. It is used to access class variables and methods. Since all instance methods are virtual in Java, this can never be null.

What is this keyword in JavaScript Javatpoint?

The this keyword is a reference variable that refers to the current object.

What is this keyword in jQuery?

The this Keyword is a reference to DOM elements of invocation. We can call all DOM methods on it. $() is a jQuery constructor and in $(this), we are just passing this as a parameter so that we can use the jQuery function and methods.

Is array a keyword in JavaScript?

Object , Array , Function and Number are not keywords, nor are they exactly "special" (whatever you think they mean) words. They're nothing more than built-in function/class types in JavaScript (you can do a typeof on them and see).

How does this work JavaScript?

In JavaScript, the this keyword allows us to: Reuse functions in different execution contexts. It means, a function once defined can be invoked for different objects using the this keyword. Identifying the object in the current execution context when we invoke a method.

How do I use this keyword in Arrow?

In short, with arrow functions there are no binding of this . In regular functions the this keyword represented the object that called the function, which could be the window, the document, a button or whatever. With arrow functions the this keyword always represents the object that defined the arrow function.

Why this keyword is undefined in event handler?

the event handler method loses its implicitly bound context. When the event occurs and the handler is invoked, the this value falls back to default binding and is set to undefined , as class declarations and prototype methods run in strict mode.

What is the use of this keyword in Java Mcq?

Explanation: “this” is an important keyword in java. It helps to distinguish between local variable and variables passed in the method as parameters.

What is keyword and example?

Keywords are the words and phrases that people type into search engines to find what they're looking for. For example, if you were looking to buy a new jacket, you might type something like “mens leather jacket” into Google. Even though that phrase consists of more than one word, it's still a keyword.

What is this and super keyword in Java?

this keyword mainly represents the current instance of a class. On other hand super keyword represents the current instance of a parent class. 2. Interaction with class constructor. this keyword used to call default constructor of the same class.

What is closure in JavaScript Mcq?

Explanation: A combination of a function object and a scope (a set of variable bindings) in which the function's variables are resolved is called a closure.

Which one of the following is not a keyword in JavaScript?

Explanation: "eval" is not a keyword and is can be used as variable.

What is the first name of JavaScript?

JavaScript Origins

In September 1995, a Netscape programmer named Brandan Eich developed a new scripting language in just 10 days. It was originally named Mocha, but quickly became known as LiveScript and, later, JavaScript.