public string refreshTotalLetters()
        {
            StringBuilder word = new StringBuilder();

            for (char c = 'A'; c <= 'Z'; c++)
            {
                if (CharactersTried.Contains(char.ToLower(c)))
                {
                    word.Append(char.ToLower(c) + " ");
                }
                else
                {
                    word.Append("_ ");
                }
            }

            return(word.ToString());
        }
 public bool guessLetter(char letter)
 {
     letter = char.ToLower(letter);
     if (!CharactersTried.Contains(letter))
     {
         CharactersTried.Add(letter);
         if (WordToGuess.Contains(letter))
         {
             CharactersNotGuessed.Remove(letter);
             return(true);
         }
         else
         {
             numberOfGuesses++;
             return(false);
         }
     }
     return(true);
 }