using System;
using System.Collections;
 
namespace Articulos.Cap04.Excepciones.Parte5
{
    public sealed class UsoNullReferenceException
    {
        public static void Main()
        {
            // Define una variable de tipo ArrayList, sin embargo 
            // aún no ha sido inicializada. Sólo con null:
            ArrayList al = null;
 
            try
            {
                // Intento de agregar un elemento a la 
                // variable ArrayList:
                al.Add ("Blog xCSw");
            }
            catch (NullReferenceException mre)
            {
                Console.WriteLine ("Mensaje de error: `{0}`", mre.Message);
            }
        }
    }
}

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