Why polymorphism matters in C Sharp (C#) - See It in Action

Why polymorphism matters

📖 Scenario: Imagine you are building a simple program to manage different types of animals in a zoo. Each animal can make a sound, but the sound is different for each animal. You want to write code that can handle any animal without knowing exactly which type it is.

🎯 Goal: Build a small C# program that shows how polymorphism lets you treat different animal types the same way while they behave differently.

📋 What You'll Learn

Create a base class called Animal with a method MakeSound().

Create two classes Dog and Cat that inherit from Animal and override MakeSound().

Create a list of Animal objects containing both Dog and Cat instances.

Use a loop to call MakeSound() on each animal and print the result.

💡 Why This Matters

🌍 Real World

Polymorphism is used in many programs where different objects share common behavior but implement it differently, like different types of animals, vehicles, or user interface elements.

💼 Career

Understanding polymorphism is essential for software developers to write clean, reusable, and extendable code, which is a key skill in professional programming jobs.

1

Create the base class Animal

Create a public class called Animal with a public virtual method MakeSound() that returns a string "Some sound".

C Sharp (C#)

// Your code here

Need a hint?

Use public virtual string MakeSound() inside the Animal class.

2

Create Dog and Cat classes inheriting Animal

Create two public classes called Dog and Cat that inherit from Animal. Override the MakeSound() method in Dog to return "Bark" and in Cat to return "Meow".

C Sharp (C#)

public class Animal
{
    public virtual string MakeSound()
    {
        return "Some sound";
    }
}

// Your code here

Need a hint?

Use public override string MakeSound() in both Dog and Cat classes.

3

Create a list of animals

Create a List<Animal> called animals and add one Dog and one Cat object to it.

C Sharp (C#)

public class Animal
{
    public virtual string MakeSound()
    {
        return "Some sound";
    }
}

public class Dog : Animal
{
    public override string MakeSound()
    {
        return "Bark";
    }
}

public class Cat : Animal
{
    public override string MakeSound()
    {
        return "Meow";
    }
}

// Your code here

Need a hint?

Use List<Animal> and add new Dog() and new Cat() to it.

4

Call MakeSound() on each animal and print

Use a foreach loop with variable animal to go through animals and print the result of animal.MakeSound().

C Sharp (C#)

using System.Collections.Generic;

public class Animal
{
    public virtual string MakeSound()
    {
        return "Some sound";
    }
}

public class Dog : Animal
{
    public override string MakeSound()
    {
        return "Bark";
    }
}

public class Cat : Animal
{
    public override string MakeSound()
    {
        return "Meow";
    }
}

List animals = new List { new Dog(), new Cat() };

// Your code here

Need a hint?

Use foreach (Animal animal in animals) and inside the loop Console.WriteLine(animal.MakeSound()).