using System;

public class Program

{

    public static void Main()

    {

        SuperClass superClassObject      = new SuperClass("SuperClass Object in SuperClass variable");

        SubClass   subClassObject        = new SubClass("SubClass Object in SubClass variable");

        SuperClass subClassObjectInSuper = new SubClass("SubClass Object in SuperClass variable");

        trial(superClassObject);

        trial(subClassObject);

        subClassObject.SubClassTrial();

        trial(subClassObjectInSuper);       

        SubClass sub = (SubClass)subClassObjectInSuper;

        sub.SubClassTrial();

    }

    private static void trial(SuperClass trialObject)

    {

        Console.WriteLine("");

        trialObject.ReplaceWithNewMethod("client");

        trialObject.ReplaceWithOverrideMethod("client");

        trialObject.SuperClassTrial();

    }

}

​

public class SuperClass

{

    protected string id;

    public SuperClass(string Id)

    {

        id = Id;

    }

    public void ReplaceWithNewMethod(string Caller)

    {

        Console.WriteLine($"{id}: SuperClass implementation: ReplaceWithNewMethod called from {Caller}");

    }

​

    public virtual void ReplaceWithOverrideMethod(string Caller)

    {

        Console.WriteLine($"{id}: SuperClass implementation: ReplaceWithOverrideMethod called from {Caller}");

    }

    public void SuperClassTrial()

    {

        ReplaceWithOverrideMethod("SuperClass");

        ReplaceWithNewMethod("SuperClass");

    }

}

​

public class SubClass : SuperClass

{

    public SubClass(string Id) : base(Id) {

    }

    public new void ReplaceWithNewMethod(string Caller)

    {

        Console.WriteLine($"{id}: SubClass implementation: ReplaceWithNewMethod called from {Caller}");

    }

​

    public override void ReplaceWithOverrideMethod(string Caller)

    {

        Console.WriteLine($"{id}: SubClass implementation: ReplaceWithOverrideMethod called from {Caller}");

    }

    public void SubClassTrial()

    {

        ReplaceWithOverrideMethod("SubClass");

        ReplaceWithNewMethod("SubClass");

    }

}

​