What is Inheritance?

Inheritance is one of the core concepts of the OOPS.The definition of Inheritance is one class deriving the property of another class is known as inheritance.

• The class from which we are going to inherit the properties then that class is known as superclass or base class or parent class.

• The class which is inheriting the property of the class is known as the subclass or derived class or child class.

class Subclass : SuperClass
    {
        //methods and fields
    }

Note: In C# we use : to inherit other classes.

Why do we need inheritance?

• Using inheritance we can reuse the code instead of rewriting the code again and again.

• Using inheritance the number of lines of code can be reduced.

Types of inheritance :

These are the types of inheritance.

1. Single Inheritance.
2. Multilevel Inheritance.
3. Multiple Inheritance.
4. Hierarchical Inheritance.
5. Hybrid Inheritance.

1. Single Inheritance :

• One class inheriting the properties of another class is called as Single inheritance.

class A
    {
        public void display()
        {
            Console.WriteLine("display() of Superclass");
        }
    }

    class B : A
    {
        public void view()
        {
            Console.WriteLine("view() of ChildClass");
        }
    }
    class Program
    {
        public static void Main()
        {
            B b = new B();
            //Using this the property of the superclass can also be called
            b.view(); //Sub class method
            b.display(); //Super class method
        }
    }
/*
Output :
view() of ChildClass
display() of Superclass
*/

2. Multilevel Inheritance :

In this type of inheritance subclass inheritance, the properties of the superclass and this superclass inherit the properties of another superclass is known as the Multilevel Inheritance.

class A
    {
        public void display()
        {
            Console.WriteLine("display() of class of A");
        }
    }

    class B : A
    {
        public void view()
        {
            Console.WriteLine("view() of class of B");
        }
    }
    class C : B
    {
        public void run()
        {
            Console.WriteLine("run() of class of C");
        }
    }
    class Program
    {
        public static void Main()
        {
            C c = new C();
            c.run();
            c.view();
            c.display();
        }
    }
*/
Output :
run() of class of C
view() of class of B
display() of class of A
*/

Note: We can access the properties of all the classes using the Object of class C because C is inheriting the class B and class B is inheriting the class A.

3. Multiple Inheritance :

In this type of inheritance one, subclass inheriting the properties of the multiple classes is known as Multiple Inheritance.

Note: The multiple inheritance is not supported in C#.

4. Hierarchical Inheritance :

In this type of inheritance from one superclass, multiple subclasses inheritances the properties this creates the hierarchical structure so, this is called as the Hierarchical Inheritance.

class Car
    {
        public void drive()
        {
            Console.WriteLine("drive() of the Car class");
        }
    }

    class Tesla : Car
    {
        public void electric()
        {
            Console.WriteLine("electric() of Tesla");
        }
    }
    class RollsRoyce : Car 
    {
        public void luxury()
        {
            Console.WriteLine("luxury() of Rolls-Royce");
        }
    }
    class Program
    {
        public static void Main()
        {
            Tesla tesla = new Tesla();

            tesla.drive();
            tesla.electric();

            RollsRoyce rolls = new RollsRoyce();

            rolls.drive();
            rolls.luxury();
        }
    }
/*
Output :
drive() of the Car class
electric() of Tesla
drive() of the Car class
luxury() of Rolls-Royce
*/

Note: In both the subclasses the basic property that is drive() is inherited along with their own methods.

5. Hybrid Inheritance :

Hybrid Inheritance is the combination of the other type of inheritance.