C# Base class Derived class sample for output of program

 internal class Program
    {
        private static void Main(string[] args)
        {

            DerivedClass1 objDerivedClass1 = new DerivedClass1();
            BaseClass objBaseClass = new DerivedClass1();
           
            //DerivedClass1 deri = new BaseClass(); Not allowed
            //Not Allowed

            objDerivedClass1.abstractProcessSalary();
            //Op :-In DerivedClass1- abstractProcessSalary
          
            objBaseClass.abstractProcessSalary();
            //Op :- In DerivedClass1- abstractProcessSalary
           
            objDerivedClass1.plainProcessSalary();
            //Op :- In DerivedClass1-virtualProcessSalary

            objDerivedClass1.virtualProcessSalary();
            //Op :- In DerivedClass1-virtualProcessSalary

            objBaseClass.virtualProcessSalary();
            //Op :- In DerivedClass1-virtualProcessSalary
           
            objBaseClass.plainProcessSalary();
            //Op :- In BaseClass- plainProcessSalary


            // DerivedClass2 objDerivedClass2 = objDerivedClass1; Not Allowed
            //Not Allowed

            BaseClass objBaseClass2 = new DerivedClass2();
            //Op :- DerivedClass2 objDerivedClass2 = objBaseClass2;  Not Allowed


            //DerivedClass1 objDerivedClass1 = objBaseClass;
            //Not Allowed


            Console.Read();
        }
    }


    internal abstract class BaseClass
    {
        public abstract void abstractProcessSalary();

        public virtual void virtualProcessSalary()
        {
            Console.WriteLine(" In BaseClass- virtualProcessSalary");

        }

        public void plainProcessSalary()
        {
            Console.WriteLine(" In BaseClass- plainProcessSalary");

        }
    }

    internal class DerivedClass1 : BaseClass
    {
        public override void abstractProcessSalary()
        {
            Console.WriteLine(" In DerivedClass1- abstractProcessSalary");
        }

        public override void virtualProcessSalary()
        {
            Console.WriteLine(" In DerivedClass1-virtualProcessSalary");
        }

        public void plainProcessSalary()
        {
            Console.WriteLine(" In DerivedClass1- plainProcessSalary");

        }

    }


    internal class DerivedClass2 : BaseClass
    {
        public override void abstractProcessSalary()
        {
            Console.WriteLine(" In DerivedClass2-abstractProcessSalary");
        }

        public override void virtualProcessSalary()
        {
            Console.WriteLine(" In DerivedClass2-virtualProcessSalary");
        }

        public void plainProcessSalary()
        {
            Console.WriteLine(" In DerivedClass2- plainProcessSalary");

        }
    }