RPGGame.GameServer.UserData.GameUser.IsValidNickname C# (CSharp) Method

        public static Boolean IsValidNickname(String nickname)
        {
            if (nickname.Length < 4 || nickname.Length > 16)
                return false;

            String bannedCh = "`~!@#$%^&*(){}[]|-+=/\\\"\';:<>,.";
            for (Int32 i = 0; i < bannedCh.Length; ++i)
            {
                if (nickname.IndexOf(bannedCh[i]) != -1)
                    return false;
            }

            return true;
        }