//IPアドレス一覧を取得
        IPAddress[] addresses = Dns.GetHostAddresses(hostName);
        foreach (IPAddress address in addresses)
        {
            Console.WriteLine("アドレス表記:" + address.ToString());

            //IPアドレスのバイト配列を,を挟んで出力
            Console.WriteLine(
                "バイト列:{0}n", string.Join(",", address.GetAddressBytes()));
        }

        Console.ReadKey();
    }
}