Program using abstract methods and abstract classes.

Write a program using abstract methods and abstract classes.

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace Csharp

{

    class AbstractClasses

    {

        public static void Main(string[] args)

        {

            cmmd obj = new cmmd();

            obj.add();

            obj.delete();

            obj.search();

            obj.update();

            Console.ReadLine();

        }

      

      

    }

    abstract class commands

    {

        public int a, b, res;

       

        public abstract void add();

            //uncommenting this lines generates an error;

        //{

        //    Console.WriteLine("The result operation is performed");

        //}

        public virtual void delete()

        {

        }

        public abstract void search();

       

        public void update()

        {

            Console.WriteLine("Performs update operations");

        }

    }

    class cmmd : commands

    {

        public override void add()

        {

            Console.WriteLine("Performs insertion operations");

        }

        public override void search()

        {

            Console.WriteLine("Performs search operations");

        }

        public override void delete()

        {

            Console.WriteLine("Performs delete operations");

        }

    }