asp.net获取客户端IP,Mac

    public class GetClientInfo
    {
        [DllImport("Iphlpapi.dll")]
        private static extern int SendARP(Int32 dest, Int32 host, ref Int64 mac, ref Int32 length);
        [DllImport("Ws2_32.dll")]
        private static extern Int32 inet_addr(string ip);

        #region 取IP
        /// <summary>
        ///
        /// </summary>
        public static string GetClientIP()
        {
            string getip;
            if (System.Web.HttpContext.Current.Request.ServerVariables["HTTP_VIA"] != null) // using proxy
            {
                getip = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString();  // Return real client IP.
            }
            else// not using proxy or can't get the Client IP
            {
                getip = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"].ToString(); //While it can't get the Client IP, it will return proxy IP.
            }
            return getip;
        }
        #endregion

        public static string GetClientMacAddress()
        {
            try
            {
                string strClientIP = System.Web.HttpContext.Current.Request.UserHostAddress.ToString().Trim();
                Int32 ldest = inet_addr(strClientIP); //目的地的ip
                Int32 lhost = inet_addr("");   //本地服务器的ip
                Int64 macinfo = new Int64();
                Int32 len = 6;
                int res = SendARP(ldest, 0, ref macinfo, ref len);
                string mac_src = macinfo.ToString("X");
                if (mac_src == "0")
                {
                    if (strClientIP == "127.0.0.1")
                        return GetServerMacAddress();
                    else
                        return null;
                }

                while (mac_src.Length < 12)
                {
                    mac_src = mac_src.Insert(0, "0");
                }

                string mac_dest = "";

                for (int i = 0; i < 11; i++)
                {
                    if (0 == (i % 2))
                    {
                        if (i == 10)
                        {
                            mac_dest = mac_dest.Insert(0, mac_src.Substring(i, 2));
                        }
                        else
                        {
                            mac_dest = "-" + mac_dest.Insert(0, mac_src.Substring(i, 2));
                        }
                    }
                }
                return mac_dest;
            }
            catch
            {
                return null;
            }
        }

        public static string GetServerMacAddress()
        {
            ManagementClass mAdapter = new ManagementClass("Win32_NetworkAdapterConfiguration");
            ManagementObjectCollection mo = mAdapter.GetInstances();
            foreach (ManagementBaseObject m in mo)
            {
                if ((bool)m["IpEnabled"] == true)
                {
                    return m["MacAddress"].ToString();
                }
            }
            mo.Dispose();
            return null;

        }