C sharp - single, multilevel, and hierarchical inheritance in C#

1. Single Inheritance

One derived class inherits from one base class.

Syntax:

class Parent {
    // base class members
}

class Child : Parent {
    // derived class members
}

 Example:

using System;
class Animal
 {
    public void Eat() {
        Console.WriteLine("Eating...");
    }
}

class Dog : Animal {
    public void Bark() {
        Console.WriteLine("Barking...");
    }
}
class Program {
    static void Main() {
        Dog d = new Dog();
        d.Eat();   // Inherited from Animal
        d.Bark();  // Defined in Dog
    }
}

Multilevel Inheritance

Definition:
A class is derived from a class which is already derived from another class.

Syntax:

class GrandParent { }

class Parent : GrandParent { }

class Child : Parent { }

 Example:

using System;

class LivingBeing {
    public void Breathe() {
        Console.WriteLine("Breathing...");
    }
}

class Animal : LivingBeing {
    public void Eat() {
        Console.WriteLine("Eating...");
    }
}

class Dog : Animal {
    public void Bark() {
        Console.WriteLine("Barking...");
    }
}

class Program {
    static void Main() {
        Dog d = new Dog();
        d.Breathe(); // From LivingBeing
        d.Eat();     // From Animal
        d.Bark();    // From Dog
    }
}

Hierarchical Inheritance

Definition:
Multiple classes inherit from a single base class.

 Syntax:

class Parent { }

class Child1 : Parent { }

class Child2 : Parent { }

 Example:

using System;

class Animal {
    public void Eat() {
        Console.WriteLine("Eating...");
    }
}

class Dog : Animal {
    public void Bark() {
        Console.WriteLine("Barking...");
    }
}

class Cat : Animal {
    public void Meow() {
        Console.WriteLine("Meowing...");
    }
}

class Program {
    static void Main() {
        Dog d = new Dog();
        d.Eat();  // Inherited from Animal
        d.Bark(); // Dog’s method

        Cat c = new Cat();
        c.Eat();  // Inherited from Animal
        c.Meow(); // Cat’s method
    }
}