C++ Inheritance & Polymorphism: Unlocking the Power of Object-Oriented Programming

C++ Inheritance and Polymorphism

Inheritance and polymorphism are two of the most important concepts in object-oriented programming. Inheritance allows programmers to create a new class from existing classes. This new class is referred to as a “derived class”, and has the same functions and properties as its parent class. Polymorphism is then used to allow derived classes to override or extend certain functions of the parent class in order to change or add behavior. In this article, we will discuss how to use inheritance and polymorphism in C++.

Inheritance in C++

In order to create a derived class in C++, you must use the keyword public in the definition. This keyword allows you access to all of the public functions and properties of the parent class. For example, if you have a base class called Person, you could create a derived class called Student like this:

class Student : public Person
{
  public:
    // Student specific functions and properties here
};

Once the derived class has been declared, you can access all of the public functions and properties of the parent class inside the derived class. This allows you to easily extend the functionality of a parent class without having to rewrite any code. For example, if the Person class has a function called getName(), you can easily override it in the Student class to return a student’s name instead of a person’s name.

Polymorphism in C++

Polymorphism is an object-oriented programming concept that allows derived classes to provide their own implementation of functions defined in the parent class. This allows for greater flexibility and extensibility when designing code, as you can create multiple subclasses of a parent class with different behavior. To enable polymorphism in C++, you must use the keyword virtual before the function declaration in the parent class.

For example, if the Person class has a virtual function called speak(), each derived class could provide its own implementation of that function. This allows the program to call the correct version of speak() based on the type of object being used. For example, Student objects could return “hello, my name is [name]”, while Teacher objects could return “hello, welcome to my class”.

Inheritance and polymorphism are incredibly powerful features of object-oriented programming, and understanding how to use them in C++ can help you create more robust and extensible programs. Once you have mastered the fundamentals, you can explore more advanced techniques such as abstract classes and interfaces.