using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Net;

using System.Text.RegularExpressions;

namespace _12获取局域网中的所有IP地址

{

    class Program

    {

        static void Main(string[] args)

        {

            IPAddress startIP = InputIPAddress("请输入开始IP地址：");

            IPAddress endIP = InputIPAddress("请输入结束IP地址：");

            int startNum;

            int endNum;

            string str1;

            string str2;

            GetBound(startIP, out startNum, out str1);

            GetBound(endIP, out endNum, out str2);

            if (str1 != str2)

            {

                Console.WriteLine("输入的IP不在同一段。");

                return;

            }

            for (int i = startNum; i < endNum; i++)

            {

                try

                {

                    IPAddress ip = IPAddress.Parse(str1 + i);

                    Console.Write("[{0}] - [", ip);

                    IPHostEntry hostEntry = Dns.GetHostEntry(ip);

                    Console.WriteLine("{0}]", hostEntry.HostName);

                }

                catch (Exception e)

                {

                    Console.WriteLine(e.Message + "]");

                }

            }

            Console.ReadKey();

        }

        static void Scan(IPAddress startIP, IPAddress endIP)

        {

        }

        static void GetBound(IPAddress ip, out int num, out string str)

        {

            string reg = @"(?<str>\d+\.\d+\.\d+\.)(?<num>\d+)";

            Match match = new Regex(reg).Match(ip.ToString());

            string numStr = match.Groups["num"].Value;

            num = Convert.ToInt32(numStr);

            str = match.Groups["str"].Value;

        }

        static IPAddress InputIPAddress(string msg)

        {

            string msgTemp = msg;

            IPAddress ip = null;

            while (true)

            {

                Console.Clear();

                Console.WriteLine(msg);

                string ipStr = Console.ReadLine();

                if (IPAddress.TryParse(ipStr, out ip))

                {

                    break;

                }

                else

                {

                    msg = "输入的\"" + ipStr + "\"格式不正确，" + msgTemp;

                }

            }

            Console.Clear();

            return ip;

        }

    }

}