调试易

using   System.Management;
使WMI获取网卡MAC地址，可以禁用网卡

//添加引用-COM-浏览-C:\WINDOWS\system32\shell32.dll-添加   
    
  private   bool   SetNetworkAdapter(bool   status)   
  {   
  const   string   discVerb   =   "禁用(&B)";   
  const   string   connVerb   =   "启用(&A)";   
  const   string   network   =   "网络和拨号连接";   
  const   string   networkConnection   =   "本地连接";   
  string   sVerb;   
    
  if   (status)   
  {   
    
  sVerb   =   connVerb;   
  }   
  else   
  {   
    
  sVerb   =   discVerb;   
  }   
    
  Shell32.Shell   sh   =   new   Shell32.Shell();   
  Shell32.Folder   folder;   
    
  folder   =   sh.NameSpace(3);       //Shell32.ShellSpecialFolderConstants.ssfCONTROLS   
  try   
  {   
  //进入控制面板的所有选项   
  foreach   (Shell32.FolderItem   myItem   in   folder.Items())   
  {   
  //进入网络和拔号连接   
  if   (myItem.Name   ==   network)   
  {   
  Shell32.Folder   fd   =   (Shell32.Folder)myItem.GetFolder;   
  foreach   (Shell32.FolderItem   fi   in   fd.Items())   
  {   
  //找到本地连接   
  if   (fi.Name.IndexOf(networkConnection)   >   -1)   
  {   
    
  //找本地连接的所有右键功能菜单   
  foreach   (Shell32.FolderItemVerb   Fib   in   fi.Verbs())   
  {   
  if   (Fib.Name   ==   sVerb)     
  {   
  Fib.DoIt();   
    
  break;   
  }   
  }   
  }   
  }   
  }   
  }   
  }   
  catch   (Exception   e)   
  {   
  MessageBox.Show(e.Message);   
  return   false;   
  }   
  ;   
  return   true;   
  }   
试试。。

http://forums.microsoft.com/china/ShowPost.aspx?PostID=3666159&SiteID=15
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Management;
using System.Collections;namespace NetWorkControl
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            NetWorkList();
        }        /// <summary>
        /// 网卡列表
        /// </summary>
        public void NetWorkList()
        {
            string manage = "SELECT * From Win32_NetworkAdapter";
            ManagementObjectSearcher searcher = new ManagementObjectSearcher(manage);
            ManagementObjectCollection collection = searcher.Get();
            List<string> netWorkList = new List<string>();            foreach (ManagementObject obj in collection)
            {
                netWorkList.Add(obj["Name"].ToString());
                
            }
           this.cmbNetWork.DataSource = netWorkList;        }        /// <summary>
        /// 禁用网卡
        /// </summary>5
        /// <param name="netWorkName">网卡名</param>
        /// <returns></returns>
        public bool DisableNetWork(ManagementObject network)
        {
            try
            {
                network.InvokeMethod("Disable", null);
                return true;
            }
            catch
            {
                return false;
            }
        }        /// <summary>
        /// 启用网卡
        /// </summary>
        /// <param name="netWorkName">网卡名</param>
        /// <returns></returns>
        public bool EnableNetWork(ManagementObject network)
        {
            try
            {
                network.InvokeMethod("Enable", null );
                return true;
            }
            catch
            {
                return false;
            }
            
        }        /// <summary>
        /// 网卡状态
        /// </summary>
        /// <param name="netWorkName">网卡名</param>
        /// <returns></returns>
        public bool NetWorkState(string netWorkName)
        {
            string netState = "SELECT * From Win32_NetworkAdapter";
            ManagementObjectSearcher searcher = new ManagementObjectSearcher(netState);
            ManagementObjectCollection collection = searcher.Get();
            foreach (ManagementObject manage in collection)
            {
                if (manage["Name"].ToString() == netWorkName )
                {
                    return true;
                }
            }
            return false;
        }        /// <summary>
        /// 得到指定网卡
        /// </summary>
        /// <param name="networkname">网卡名字</param>
        /// <returns></returns>
        public ManagementObject NetWork(string networkname)
        {
            string netState = "SELECT * From Win32_NetworkAdapter";            ManagementObjectSearcher searcher = new ManagementObjectSearcher(netState);
            ManagementObjectCollection collection = searcher.Get();            foreach (ManagementObject manage in collection)
            {
                if (manage["Name"].ToString() == networkname)
                {
                    return manage;
                }
            }            
            return null;
        }        private void btnStart_Click(object sender, EventArgs e)
        {
            if (NetWorkState(this.cmbNetWork.SelectedValue.ToString()))
            {
                if (!EnableNetWork(NetWork(this.cmbNetWork.SelectedValue.ToString())))
                {
                    MessageBox.Show("开启网卡失败!");
                }
                else
                {
                    MessageBox.Show("开启网卡成功!");
                }
            }
            else
            {
                MessageBox.Show("网卡己开启!");
            }            NetWorkList();
        }        private void btnStop_Click(object sender, EventArgs e)
        {            if (NetWorkState(this.cmbNetWork.SelectedValue.ToString()))
            {
                if (!DisableNetWork(NetWork(this.cmbNetWork.SelectedValue.ToString())))
                {
                    MessageBox.Show("禁用网卡失败!");
                }
                else
                {
                    MessageBox.Show("禁用网卡成功!");
                }
            }
            else
            {
                MessageBox.Show("网卡己禁用!");
            }            NetWorkList();
        }    }
}
摘的一段,希望对你有帮助

楼上的什么系统，Disable和Enable是不能调用的，至少在XP里