c#.net中類的覆寫(override)

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());
   }
}