How do you define a class in JavaScript ES6?
A). class ClassName { constructor() {} }
B). function ClassName() { constructor() {} }
C). class ClassName() { constructor {} }
D). function class ClassName { constructor() {} }
What will console.log(car.make); output if var car = {make: 'Toyota', model: 'Corolla'};?
A). Toyota
B). Corolla
C). Undefined
D). Error
What is the purpose of the this keyword in a constructor function?
A). It refers to the new object being created.
B). It refers to the global object.
C). It refers to the current object.
D). It refers to the parent object.
How can you check if the age property exists in the person object?
A). 'age' in person
B). person.has('age')
C). person.contains('age')
D). person.hasOwnProperty('age')
How do you define a constructor function for creating Car objects?
A). function Car(make, model) { this.make = make; this.model = model; }
B). Car(make, model) { this.make = make; this.model = model; }
C). var Car = function(make, model) { this.make = make; this.model = model; };
D). Car = function(make, model) { this.make = make; this.model = model; };
How can you delete the age property from the person object?
A). delete person.age;
B). remove person.age;
C). person.age = null;
D). person.age.delete;
How do you access the value of the name property in the object var person = {name: 'John', age: 30};?
A). person['name']
B). person.name
C). person->name
D). person::name
How do you define a method named greet in an object var person = {};?
A). person.greet = function() {};
B). person.greet: function() {};
C). person.greet = () {};
D). person.greet = function {};
What will the following code output? console.log(person['age']); if var person = {name: 'John'};
A). 30
B). John
C). undefined
D). null
What is the output of console.log(person.greet()); if var person = {greet: function() {return 'Hello';}};?
A). Hello
B). Undefined
C). Error
D). Hello