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1:

// versioning.cs

// CS0114 expected

public class MyBase 

{

   public virtual string Meth1() 

   {

      return "MyBase-Meth1";

   }

   public virtual string Meth2() 

   {

      return "MyBase-Meth2";

   }

   public virtual string Meth3() 

   {

      return "MyBase-Meth3";

   }

}



class MyDerived : MyBase 

{

   // Overrides the virtual method Meth1 using the override keyword:


   public override string Meth1() 

   {

      return "MyDerived-Meth1";

   }

   // Explicitly hide the virtual method Meth2 using the new

   // keyword:


   public new string Meth2() 

   {

      return "MyDerived-Meth2";

   }

   // Because no keyword is specified in the following declaration

   // a warning will be issued to alert the programmer that 

   // the method hides the inherited member MyBase.Meth3():


   public string Meth3() 

   {

      return "MyDerived-Meth3";

   }



   public static void Main() 

   {

      MyDerived mD = new MyDerived();

      MyBase mB = (MyBase) mD;



      System.Console.WriteLine(mB.Meth1());

      System.Console.WriteLine(mB.Meth2());

      System.Console.WriteLine(mB.Meth3());

   }



}

output:




MyDerived-Meth1

MyBase-Meth2

MyBase-Meth3

 

 

Code Discussion

Hiding a base class member from a derived class isn't an error in C#. This feature enables you to make changes in the base class without breaking other libraries that inherit this base class. For example, at some point you could have the following classes: