private static void PerformEncryptOperation(out string plainText, out string cipherText, out int shift) { AppMessage("Welcome to encryption mode \nEnter message to encrypt"); plainText = Console.ReadLine(); shift = 0; cipherText = string.Empty; if (plainText != "") { try { AppMessage("Enter the shift"); shift = int.Parse(Console.ReadLine()); if (shift <= 26 && shift > 0) { AppMessage("Cipher is"); cipherText = new string(CaesarCipher.Encrypt(plainText, shift)); Console.WriteLine(cipherText); } else { ErrorMessage("Enter a number between 1 to 26"); } } catch (Exception e) { ErrorMessage(e.Message); } } else { ErrorMessage("Invalid input"); } }