using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;

namespace Tech_Demo
{
    public class ArpUtil
    {
        /// <summary>
        /// 引入windowsAPI
        /// </summary>

        //用于转换ip地址  
        [DllImport("ws2_32.dll")]
        public static extern int inet_addr(string cp);

        //用于发送APR包（根据APR协议！）  
        [DllImport("IPHLPAPI.dll")]
        public static extern int SendARP(int DestIP, int ScrIP, ref long pMacAddr, ref int PhyAddrLen);

        /// <summary>
        /// 根据ARP映射获取指定IP的MAC地址
        /// </summary>
        /// <param name="ip"></param>
        /// <returns></returns>
        public string GetMACAddressByIP(string ip)
        {
            StringBuilder macRouteBuilder = new StringBuilder();
            string macRoute;
            try
            {
                int ldest = inet_addr(ip); //将IP地址从 点数格式转换成无符号长整型  
                long macinfo = new long();
                int len = 6;
                //SendARP函数发送一个地址解析协议(ARP)请求获得指定的目的地IPv4地址相对应的物理地址  
                SendARP(ldest, 0, ref macinfo, ref len);
                string TmpMac = Convert.ToString(macinfo, 16).PadLeft(12, '0'); //转换成16进制  
                //  
                for (int i = 10; i >= 0; i = i - 2) //反过来读取，原因可以查看接口函数sendApr！  
                {
                    macRouteBuilder.Append(TmpMac.Substring(i, 2).ToUpper());
                    if (i >= 2)
                    {
                        macRouteBuilder.Append("-");
                    }
                }
            }
            catch (Exception Mye)
            {
                macRouteBuilder.Append("获取远程主机的MAC错误：");
                macRouteBuilder.Append(Mye.ToString());
            }

            macRoute = macRouteBuilder.ToString();
            return macRoute;
        }

        /// <summary>
        /// 获取ARP查询字符串
        /// </summary>
        /// <returns></returns>
        private static string GetArpResult()
        {
            Process p = null;
            string output = string.Empty;
            try
            {
                p = Process.Start(new ProcessStartInfo("arp", "-a -n 192.168.0.105")
                {
                    CreateNoWindow = true,
                    UseShellExecute = false,
                    RedirectStandardOutput = true
                });
                output = p.StandardOutput.ReadToEnd();
            }
            catch (Exception ex)
            {
                throw new Exception("IPInfo: Error Retrieving 'arp -a' Results", ex);
            }
            finally
            {
                if (p != null)
                {
                    p.Close();
                }
            }

            return output;
        }

        /// <summary>
        /// 获取IP地址与Mac地址对应数据表
        /// </summary>
        /// <returns>Mac-IP</returns>
        public static List<string[]> GetIpInfo()
        {
            try
            {
                var list = new List<string[]>();
                var arpResult = GetArpResult();
                foreach (var arp in arpResult.Split(new char[] { '\n', '\r' }))
                {
                    if (!string.IsNullOrEmpty(arp))
                    {
                        var oArp = arp.Split(new char[] { ' ', '\t' });
                        var pieces = (from piece in oArp
                            where !string.IsNullOrEmpty(piece)
                            select piece).ToArray();
                        if (pieces.Length == 3)
                        {
                            //pieces[1]Mac
                            //pieces[0]IP
                            list.Add(new string[2] { pieces[1], pieces[0] });
                        }
                    }
                }

                return list;
            }
            catch (Exception ex)
            {
                throw new Exception("IPInfo: Error Parsing 'arp -a' results", ex);
            }
        }
    }
}