using System;  

using System.Collections.Generic;  

using System.Linq;  

using System.Text;  

namespace OverrideAndNew2  

{  

    public class Program  

    {  

        public void Main()  

        {  

            // Declare objects of the derived classes and test which version  

            // of ShowDetails is run, base or derived.  

            TestCars1();  

            // Declare objects of the base class, instantiated with the  

            // derived classes, and repeat the tests.  

            TestCars2();  

            // Declare objects of the derived classes and call ShowDetails  

            // directly.  

            TestCars3();  

            // Declare objects of the base class, instantiated with the  

            // derived classes, and repeat the tests.  

            TestCars4();  

        }  

        public static void TestCars1()  

        {  

            System.Console.WriteLine("\nTestCars1");  

            System.Console.WriteLine("----------");  

            Car car1 = new Car();  

            car1.DescribeCar();  

            System.Console.WriteLine("----------");  

            // Notice the output from this test case. The new modifier is  

            // used in the definition of ShowDetails in the ConvertibleCar  

            // class.

            ConvertibleCar car2 = new ConvertibleCar();  

            car2.DescribeCar();  

            System.Console.WriteLine("----------");  

        }  

        // Output:  

        // TestCars1  

        // ----------  

        // Four wheels and an engine.  

        // Standard transportation.  

        // ----------  

        // Four wheels and an engine.  

        // Standard transportation.  

        // ----------  

        // Four wheels and an engine.  

        // Carries seven people.  

        // ----------  

        public static void TestCars2()  

        {  

            System.Console.WriteLine("\nTestCars2");  

            System.Console.WriteLine("----------");  

            var cars = new List<Car> { new Car(), new ConvertibleCar()};  

            foreach (var car in cars)  

            {  

                car.DescribeCar();  

                System.Console.WriteLine("----------");  

            }  

        }  

        // Output:  

        // TestCars2  

        // ----------  

        // Four wheels and an engine.  

        // Standard transportation.  

        // ----------  

        // Four wheels and an engine.  

        // Standard transportation.  

        // ----------  

        // Four wheels and an engine.  

        // Carries seven people.  

        // ----------  

        public static void TestCars3()  

        {  

            System.Console.WriteLine("\nTestCars3");  

            System.Console.WriteLine("----------");  

            ConvertibleCar car2 = new ConvertibleCar();  

            car2.ShowDetails();  

        }  

        // Output:  

        // TestCars3  

        // ----------  

        // A roof that opens up.  

        // Carries seven people.  

        public static void TestCars4()  

        {  

            System.Console.WriteLine("\nTestCars4");  

            System.Console.WriteLine("----------");  

            Car car2 = new ConvertibleCar();  

            car2.ShowDetails();  

        }  

        // Output:  

        // TestCars4  

        // ----------  

        // Standard transportation.  

        // Carries seven people.  

    }  

    // Define the base class, Car. The class defines two virtual methods,  

    // DescribeCar and ShowDetails. DescribeCar calls ShowDetails, and each derived  

    // class also defines a ShowDetails method. The example tests which version of  

    // ShowDetails is used, the base class method or the derived class method.  

    class Car  

    {  

        public void DescribeCar()  

        {  

            System.Console.WriteLine("Four wheels and an engine.");  

            ShowDetails();  

        }  

        public void ShowDetails()  

        {  

            System.Console.WriteLine("Standard transportation.");  

        }  

    }  

    // Define the derived classes.  

    // Class ConvertibleCar uses the new modifier to acknowledge that ShowDetails  

    // hides the base class method.  

    class ConvertibleCar : Car  

    {  

        public new void ShowDetails()  

        {  

            System.Console.WriteLine("A roof that opens up.");  

        }  

    }  

​

}