C#根据本地IP获取MAC地址（Windows API SendARP函数方式）

        [DllImport("Iphlpapi.dll")]
        private static extern int SendARP(Int32 dest, Int32 host, ref Int32 mac, ref Int32 length);

        [DllImport("Ws2_32.dll")]
        private static extern Int32 inet_addr(string ip);

        /// <summary>
        /// 根据本地IP地址获取MAC地址（Windows API函数方式）
        /// </summary>
        /// <param name="IP"></param>
        /// <returns></returns>
        public static string GetMACFromIP(string IP)
        {
            string strRet = "Unknown";

            string strIPPattern = @"^\d+\.\d+\.\d+\.\d+$";

            Regex objRex = new Regex(strIPPattern);

            if (objRex.IsMatch(IP) == true)
            {
                Int32 intDest = inet_addr(IP);
                Int32[] arrMAC = new Int32[2];
                Int32 intLen = 6;

                int intResult = SendARP(intDest, 0, ref arrMAC[0], ref intLen);

                if (intResult == 0)
                {
                    Byte[] arrbyte = new Byte[8];
                    arrbyte[5] = (Byte)(arrMAC[1] >> 8);
                    arrbyte[4] = (Byte)arrMAC[1];
                    arrbyte[3] = (Byte)(arrMAC[0] >> 24);
                    arrbyte[2] = (Byte)(arrMAC[0] >> 16);
                    arrbyte[1] = (Byte)(arrMAC[0] >> 8);
                    arrbyte[0] = (Byte)arrMAC[0];

                    StringBuilder strbMAC = new StringBuilder();

                    for (int intIndex = 0; intIndex < 6; intIndex++)
                    {
                        if (intIndex > 0) strbMAC.Append("-");
                        strbMAC.Append(arrbyte[intIndex].ToString("X2"));
                    }
                    strRet = strbMAC.ToString();
                }
            }

            return strRet;
        }

                //根据本地IP地址获取MAC地址：00-E0-4C-44-17-F4
                var macd1 = NetTools.GetMACFromIP("192.168.0.172");