Codecademy export

Program.cs

using System;

namespace CaesarCipher
{
  class Program
  {
    static void Main(string[] args)
    {
      char[] alphabet = new char[] {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'};
      Console.WriteLine("What would your message be?");
      string message = Console.ReadLine();
      
      Console.WriteLine("Would you like to code or decode the message?");
      string answer1 = Console.ReadLine();
      if (answer1 == "Code" || answer1 == "code") {
      char[] secretMessage = message.ToCharArray();
      char[] encryptedMessage = new char[secretMessage.Length];
      for (int i = 0; i < secretMessage.Length; i++) {
        char letter = secretMessage[i];
        int letterPosition = Array.IndexOf(alphabet, letter);
        int newLetterPosition = letterPosition + 3;
        char letterEncoded = alphabet[newLetterPosition];
        encryptedMessage[i] = letterEncoded;
      }
      string end_message = String.Join("", encryptedMessage);
      Console.WriteLine(end_message);
    } else {
        char[] secretMessage = message.ToCharArray();
      char[] encryptedMessage = new char[secretMessage.Length];
      for (int i = 0; i < secretMessage.Length; i++) {
        char letter = secretMessage[i];
        int letterPosition = Array.IndexOf(alphabet, letter);
        int newLetterPosition = letterPosition - 3;
        char letterEncoded = alphabet[newLetterPosition];
        encryptedMessage[i] = letterEncoded;
      }
      string end_message = String.Join("", encryptedMessage);
      Console.WriteLine(end_message);
      }
    
    }
    }
  }