Q
How do you check if an object has a property 'col...

Answer & Solution

Answer: Option A
Solution:
The 'in' operator is used to check if an object has a specific property.
Related Questions on Average

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 get the number of properties in an obj...

A). Object.keys(book).length

B). book.countProperties()

C). book.totalProperties()

D). book.length()

How can you remove a property 'email' from an obj...

A). delete user.email;

B). user.remove('email');

C). user.email = null;

D). user.pop('email');

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 {};

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 access nested properties in an object?

A). obj.property.nestedProp (B21)

B). obj['property']['nestedProp'] (C21)

C). obj.property['nestedProp'] (D21)

D). obj['property'].nestedProp (E21)

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...

What does the Object.values(obj) method 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.

What is the purpose of the 'this' keyword in a co...

A). It refers to the new object bei...

B). It refers to the global object.

C). It refers to the current object.

D). It refers to the parent object.

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.