System.Net.Cookie.DomainCharsTest C# (CSharp) Method

        private static bool DomainCharsTest(string name)
        {
            if (name == null || name.Length == 0)
            {
                return false;
            }
            for (int i = 0; i < name.Length; ++i)
            {
                char ch = name[i];
                if (!((ch >= '0' && ch <= '9') ||
                      (ch == '.' || ch == '-') ||
                      (ch >= 'a' && ch <= 'z') ||
                      (ch >= 'A' && ch <= 'Z') ||
                      (ch == '_')))
                {
                    return false;
                }
            }
            return true;
        }