How do you get the number of properties in an obj...
A). Object.keys(book).length
B). book.countProperties()
C). book.totalProperties()
D). book.length()
How do you access a property called 'name' from an...
A). person.name
B). person['name']
C). person->name
D). person::name
How do you define a method 'sayHello' in an obj...
A). person.sayHello = function() {};
B). person.sayHello: function() {};
C). person.sayHello = () {};
D). person.sayHello = function {};
What is the output of console.log(obj.prop) if ob...
A). It prints undefined.
B). It throws an error.
C). It prints null.
D). It prints true.
How do you define a constructor function for crea...
A). function Car(make, model) { thi...
B). Car(make, model) { this.make = m...
C). var Car = function(make, model) ...
D). Car = function(make, model) { t...
How do you add a method to an object created wit...
A). this.methodName = function() {}
B). this.methodName: function() {};
C). this.methodName = () {}
D). this.methodName: () {}
How do you create an instance of the 'Car' objec...
A). var myCar = new Car('Toyota', ...
B). var myCar = Car('Toyota', 'Corol...
C). var myCar = create Car('Toyota',...
D). var myCar = construct Car('Toyo...
How do you iterate over all properties of an obj...
A). for (var prop in person)
B). forEach(prop in person)
C). for (var prop of person)
D). forEach(prop of person)
What is the correct way to create an empty object...
A). var obj = {};
B). var obj = ();
C). var obj = [];
D). var obj = <{}>;
What does Object.keys(obj) return?
A). An array of object keys.
B). An array of object values.
C). An array of object properties.
D). An array of object methods.