public string Cifrar312(string texto)
        {
            string result = "";

            for (int i = 0;i<=texto.Length -1;i++)
            {

               result += Convert.ToChar(
                         Convert.ToInt32(
                         ((int)texto[i]).ToString("000").Substring(2, 1) +
                         ((int)texto[i]).ToString("000").Substring(0, 1) + 
                         ((int)texto[i]).ToString("000").Substring(1, 1)));

            }

            return result;
        }

        public string DesCifrar312(string texto)
        {

            string result = "";

            for (int i = 0; i <= texto.Length - 1; i++)
            {
                result += Convert.ToChar(
                          Convert.ToInt32(
                          ((int)texto[i]).ToString("000").Substring(1, 1) + 
                          ((int)texto[i]).ToString("000").Substring(2, 1) + 
                          ((int)texto[i]).ToString("000").Substring(0, 1)));
            }

            return result;
        }


"nƛoΊǿɣoǻnnnnnnnnnnǿIJ" = Cifrar312("PeroEstoKeeeeeeeeees?");