Method overriding in Javascript - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is method overriding in JavaScript?

Method overriding is when a child class provides its own version of a method that already exists in its parent class. The child method replaces the parent method when called on the child object.

beginner

How do you override a method in a JavaScript class?

You create a method in the child class with the same name as the method in the parent class. When you call this method on the child object, the child's version runs instead of the parent's.

beginner

What happens if you call a method on a child object that is overridden?

The child class's method runs, not the parent class's method. This lets the child customize or change behavior inherited from the parent.

intermediate

Can you still call the parent class's method from the overridden method in the child class?

Yes, by using the super keyword. For example, inside the child method you can call super.methodName() to run the parent method.

beginner

Why is method overriding useful in programming?

It allows child classes to change or extend the behavior of parent classes without changing the parent code. This helps reuse code and customize behavior easily.

What keyword is used in JavaScript to call a parent class's method from an overridden method?

A this

B parent

C super

D base

The super keyword is used to access methods from the parent class inside the child class.

If a child class overrides a method, which method runs when called on a child object?

A Child class method

B Parent class method

C Both methods run

D Error occurs

The child class method overrides the parent method and runs instead.

What is the main purpose of method overriding?

A To hide parent class methods

B To change or extend behavior inherited from the parent

C To create new methods unrelated to the parent

D To reuse parent class methods without changes

Method overriding lets child classes change or extend the behavior inherited from the parent class.

Which of the following is true about method overriding in JavaScript classes?

A Child class methods must have different names than parent methods

B Parent methods always run before child methods

C Overriding is not possible in JavaScript

D Child class methods replace parent methods with the same name

Child class methods with the same name replace parent methods when called on child objects.

How do you define a method in a child class that overrides a parent method?

A Use the same method name in the child class

B Use a different method name in the child class

C Use the override keyword before the method

D Use the extends keyword inside the method

Overriding happens by defining a method with the same name in the child class.

Explain method overriding in JavaScript and how it helps customize behavior in child classes.

Think about how child classes can change what parent classes do.

Describe how to call a parent class's method from an overridden method in a child class.

Remember the special keyword for accessing parent methods.