Q
How do you get the number of properties in an obj...

Answer & Solution

Answer: Option B
Solution:
You can use Object.keys(obj).length to get the number of properties in an object.
Related Questions on Average

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.

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 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 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 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)

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 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 add a new property 'age' with value 25...

A). person.age = 25;

B). person['age'] = 25;

C). person.add('age', 25);

D). person.push('age', 25);

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.