private static string EncryptWithKey(string text, char key)
{
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' };
char[] selectedCipher = ChooseArray(key);
string encryptedString = String.Empty;
foreach (char character in text)
{
if (!char.IsLetter(character))
{
encryptedString += character;
}
else if (char.IsUpper(character))
{
char[] upperAlpha = alphabet.ArrayToUpper();
char[] upperSelectedCipher = selectedCipher.ArrayToUpper();
//int index = alphabet.ToString().IndexOf(character);
int index = Array.IndexOf(upperAlpha, character);
encryptedString += upperSelectedCipher[index];
}
else
{
int index = Array.IndexOf(alphabet, character);
encryptedString += selectedCipher[index];
}
}
return(encryptedString);
}