public static void SbmMasa()
        {
            bool r = true;

            while (r)
            {
                Console.ForegroundColor = ConsoleColor.Green;
                sbyte[] a = new sbyte[9] {
                    1, 2, 3, 4, 5, 6, 7, 8, 9
                };
                Console.WriteLine("Comandos disponibles:\n{0}: Conversor Kilogramos.\n{1}: Conversor Gramos.", a[0], a[1]);
                Console.WriteLine("{0}: Conversor Toneladas (métricas).\n{1}: Conversor Toneladas Cortas.\n{2}: Conversor Toneladas Largas", a[2], a[3], a[4]);
                Console.WriteLine("{0}: Conversor Libras.\n{1}: Conversor Onzas.\n{2}: Conversor \"Stones\".", a[5], a[6], a[7]);
                Console.WriteLine("{0}: Volver al menú.", a[8]);

                sbyte i = 1;
                try
                {
                    Console.Write(">> ");
                    i = Convert.ToSByte(Console.ReadLine());
                }
                catch (Exception e) when(e.GetType() != typeof(FormatException))
                {
                    Console.WriteLine(e.Message);
                }
                catch (FormatException e)
                {
                    Console.WriteLine("El valor introducizo no es numérico.");
                    Console.WriteLine(e.Message);
                }
                finally
                {
                    if (i == a[0])
                    {
                        Transformador.CmdKg();
                        r = true;
                    }
                    else if (i == a[1])
                    {
                        Transformador.CmdGr();
                        r = true;
                    }
                    else if (i == a[2])
                    {
                        Transformador.CmdT();
                        r = true;
                    }
                    else if (i == a[3])
                    {
                        Transformador.CmdUsT();
                        r = true;
                    }
                    else if (i == a[4])
                    {
                        Transformador.CmdUkT();
                        r = true;
                    }
                    else if (i == a[5])
                    {
                        Transformador.CmdLb();
                        r = true;
                    }
                    else if (i == a[6])
                    {
                        Transformador.CmdOz();
                        r = true;
                    }
                    else if (i == a[7])
                    {
                        Transformador.CmdSt();
                        r = true;
                    }
                    else if (i == a[8])
                    {
                        r = false;
                        Console.Clear();
                    }
                    else
                    {
                        Console.WriteLine("Comando no encontrado.");
                        r = true;
                    }
                }
            }
        }