ConActionT.cs

using System;
using System.Windows.Forms;

namespace Articulos.Cap03
{
    public class ConActionT
    {
        public static void Main()
        {
            Action<string> mm;

            if (Environment.GetCommandLineArgs().Length > 1)
            {
                mm = MostrarEnVentana;
            }
            else
            {
                mm = Console.WriteLine;
            }

            mm("Blog xCSw");
        }

        private static void MostrarEnVentana(string mensaje)
        {
            MessageBox.Show(mensaje);
        }
    }
}