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)
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 {};
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');
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 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 do you define a method inside a class in JavaScript ES6?
A). methodName() {}
B). this.methodName = function() {}
C). function methodName() {}
D). methodName: function() {}
What will console.log(newCar.make); output if class Car { constructor(make) { this.make = make; }} var newCar = new Car('Honda');?
A). Honda
B). Car
C). Undefined
D). Error
What will the following code output? console.log(person['age']); if var person = {name: 'John'};
A). 30
B). John
C). undefined
D). null
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 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;