System.DomainNameHelper.IsASCIILetter C# (CSharp) 메소드

        private static bool IsASCIILetter(char character, ref bool notCanonical) {

            if (character >= 'a' && character <= 'z')   return true;

            if (character >= 'A' && character <= 'Z')
            {
                if (!notCanonical) notCanonical = true;
                return true;
            }
            return false;
        }
        //