获取MAC地址的几种方式

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Runtime.InteropServices;
namespace WebApplication3
{
    public partial class a1 : System.Web.UI.Page
    {
        [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);
        protected void Page_Load(object sender, EventArgs e)
        {
            Response.Write(GetClientMAC());
            Response.Write("<br>");
            Response.Write(gett());
            return;
        }
        ///<summary>
        ///得到客户端ip
        ///</summary>
        ///<returns>ip</returns>
        private static string GetClientIP()
        {
            string result = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
            if (null == result || result == String.Empty)
            {
                result = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
            }
            if (null == result || result == String.Empty)
            {
                result = HttpContext.Current.Request.UserHostAddress;
            }
            return result;
        }


        ///<summary>
        /// 利用客户端ip得到客户端mac
        ///</summary>
        ///<param name="remoteip">客户端ip</param>
        ///<returns>int16类型的mac</returns>
        static private Int64 getremotemac(string remoteip)
        {
            Int32 ldest = inet_addr(remoteip);
            try
            {
                Int64 macinfo = new Int64();
                Int32 len = 6;
                int res = SendARP(ldest, 0, ref   macinfo, ref   len);
                return macinfo;
            }
            catch (Exception err)
            {
                throw err;
            }
            return 0;
        }


        ///<summary>
        /// int64类型的mac转换成正确的客户端mac
        ///</summary>
        ///<returns>mac</returns>
        public static string GetClientMAC()
        {
            Int64 macid = getremotemac(GetClientIP());
            if (macid == 0)
                return "0";
            string beforeMacAddr = Convert.ToString(macid, 16);
            string endMacAddr = "";
            string[] macArray = new string[6];
            for (int i = 0; i < 6; i++)
            {
                macArray[i] = beforeMacAddr.Substring(i * 2, 2);
            }
            for (int i = 0; i < 6; i++)
            {
                endMacAddr += macArray[5 - i] + "-";
            }
            endMacAddr = endMacAddr.Substring(0, endMacAddr.Length - 1);
            endMacAddr = endMacAddr.ToUpper();
            return endMacAddr;
        }
        public static string gett()
        {
            string userip = HttpContext.Current.Request.UserHostAddress;
            string strClientIP = 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 (userip == "127.0.0.1")
                    return "正在访问Localhost!";
                else
                    return "欢迎来自IP为" + userip + "的朋友！" + "<br>";
            }

            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 "欢迎来自IP为" + userip + "<br>" + ",MAC地址为" + mac_dest + "的朋友！" + "<br>";
        }

    }
}

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="a1.aspx.cs" Inherits="WebApplication3.a1" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
<div style="display:none">  
        <OBJECT id=locator classid=CLSID:76A64158-CB41-11D1-8B02-00600806D9B6 VIEWASTEXT></OBJECT>  
<OBJECT id=foo classid=CLSID:75718C9A-F029-11d1-A1AC-00C04FB6C223></OBJECT>  
        </div>  
    <form id="formfoo" name="formfoo"  runat="server">
    <div>
<br/>MAC地址：<input type="text" name="macAddress">*仅IE浏览器下 显示，如果不显示 IE浏览器需要做设置允许未标记的activex
<br/>IP地址：<input type="text" name="ipAddress">
<br/>主机名：<input type="text" name="hostName">
    </div>

<script language="javascript">
var sMacAddr="";
var sIPAddr="";
var sDNSName="";
var service = locator.ConnectServer();
service.Security_.ImpersonationLevel=3;
service.InstancesOfAsync(foo, ‘Win32_NetworkAdapterConfiguration‘);
</script>
<script FOR="foo" EVENT="OnObjectReady(objObject,objAsyncContext)" LANGUAGE="JScript">
         if(objObject.IPEnabled != null && objObject.IPEnabled != "undefined" && objObject.IPEnabled == true){
                           if(objObject.IPEnabled && objObject.IPAddress(0) !=null && objObject.IPAddress(0) != "undefined")
                                         sIPAddr = objObject.IPAddress(0);
                           if(objObject.MACAddress != null &&objObject.MACAddress != "undefined")
                     sMacAddr = objObject.MACAddress;
                           if(objObject.DNSHostName != null &&objObject.DNSHostName != "undefined")
                                         sDNSName = objObject.DNSHostName;
          }
</script>

<script FOR="foo" EVENT="OnCompleted(hResult,pErrorObject, pAsyncContext)" LANGUAGE="JScript">
formfoo.macAddress.value=sMacAddr;
formfoo.ipAddress.value=sIPAddr;
formfoo.hostName.value=sDNSName;
</script>
    </form>
</body>
</html>