Basics object-oriented programming with C#: Polymorphism

Welcome to the wild and wonderful world of polymorphism, my fellow programmers! Polymorphism is one of the fundamental concepts of object-oriented programming (OOP) and it allows us to use a single interface to represent multiple types of objects. It’s like magic, but with less wand waving and more code typing.

In C#, polymorphism is achieved through the use of virtual and override keywords, abstract classes, and interface.

Let’s start with the virtual override keywords. The virtual keyword is used to indicate that a method or property can be overridden in a derived class. For example, let's say we have a base class called "Animal" with a virtual method called "Speak()".

public class Animals
{
    public virtual void Speak()
    {
        Console.WriteLine("Animal can't speak.");
    }
}

Let’s say we have a derived class called “Dogs” that inherits from the “Animals” class. We can override the “Speak()” method in the “Dogs” class to make the dogs bark.

class Dogs : Animals
{
    public override void Speak()
    {
        Console.WriteLine("Woof woof");
    }
}

Now, if we create an instance of the “Dogs” class and call the “Speak()” method, it will print “Woof woof” instead of “Animals can’t speak.”