How do you iterate over all properties of an object var person = {name: 'John', age: 30};?
A). for (var key in person)
B). for (var key of person)
C). forEach(key in person)
D). forEach(key of person)
What is the output of console.log(person.greet()); if var person = {greet: function() {return 'Hello';}};?
A). Hello
B). Undefined
C). Error
D). Hello
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 add a new property gender with value male to the person object?
A). person.gender = 'male';
B). person.gender = male;
C). person.gender = ['male'];
D). person[gender] = 'male';
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() {} }
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 inherit properties and methods from another class in JavaScript ES6?
A). class SubClass extends SuperClass {}
B). class SubClass inherits SuperClass {}
C). class SubClass implements SuperClass {}
D). class SubClass super SuperClass {}
How do you create an instance of the Car object using the constructor function?
A). var myCar = new Car('Toyota', 'Corolla');
B). var myCar = Car('Toyota', 'Corolla');
C). var myCar = create Car('Toyota', 'Corolla');
D). var myCar = construct Car('Toyota', 'Corolla');