如何关闭所有与互联网的连接？答案

【问题标题】：How to close all connections to internet?如何关闭所有与互联网的连接？
【发布时间】：2018-09-16 01:22:53
【问题描述】：

我有一个为公共图书馆编写的基本 .NET 应用程序，它只是启用和禁用 Internet 访问。它通过切换防火墙来实现这一点，并利用 UAC 提示输入管理员凭据。

它运行良好，但不会关闭现有连接。例如，Facebook Messenger 保持连接打开，并在启用防火墙并阻止所有 Internet 访问后很长时间继续工作。

理想情况下，我想关闭与本地子网外部的所有连接。如果这不可能，关闭端口 80/443 上的所有连接也可以。我想避免不得不杀死打开这些连接的实际进程，而宁愿只杀死连接本身。

我如何做到这一点？

【问题讨论】：

标签： c# .net network-programming

【解决方案1】：

我知道这不是你想要的你可能会暴力破解网络适配器。重新启用后，它将允许您的防火墙规则生效

基本上，没有适配器不能上网

Disable network adapter without WMI

Netsh

Process.Start("cmd.exe","/c netsh interface set interface 'Local Area Connection' DISABLED")

Disable/enable network adapter using WMI

获取网络广告商

public static List<NetworkAdapter> GetAllNetworkAdapter()
{
   List<NetworkAdapter> allNetworkAdapter = new List<NetworkAdapter>();

   // Manufacturer <> 'Microsoft'to get all none virtual devices. 
   // Because the AdapterType property will be null if the NetworkAdapter is  
   // disabled, so we do not use NetworkAdapter = 'Ethernet 802.3' or  
   // NetworkAdapter = 'Wireless’ 
   string strWQuery = "SELECT DeviceID, ProductName, "
                        + "NetEnabled, NetConnectionStatus "
                        + "FROM Win32_NetworkAdapter "
                        + "WHERE Manufacturer <> 'Microsoft'";

   ManagementObjectCollection networkAdapters = WMIOperation.WMIQuery(strWQuery);
   foreach (ManagementObject moNetworkAdapter in networkAdapters)
   {
      try
      {
         allNetworkAdapter.Add(new NetworkAdapter(
                                                   Convert.ToInt32(moNetworkAdapter["DeviceID"].ToString()),
                                                   moNetworkAdapter["ProductName"].ToString(),
                                                   (Convert.ToBoolean(moNetworkAdapter["NetEnabled"].ToString()))
                                                      ? (int)EnumNetEnabledStatus.Enabled
                                                      : (int)EnumNetEnabledStatus.Disabled,
                                                   Convert.ToInt32(moNetworkAdapter["NetConnectionStatus"].ToString()
                                                                  )));
      }
      catch (NullReferenceException)
      {
         // Ignore some other devices (like the bluetooth), that need user  
         // interaction to enable or disable. 
      }
   }

   return allNetworkAdapter;
}

启用禁用

public int EnableOrDisableNetworkAdapter(string strOperation)
{
   int resultEnableDisableNetworkAdapter = (int)EnumEnableDisableResult.Unknow;
   ManagementObject crtNetworkAdapter = new ManagementObject();

   string strWQuery = string.Format("SELECT DeviceID, ProductName, "
                                    + "NetEnabled, NetConnectionStatus "
                                    + "FROM Win32_NetworkAdapter " + "WHERE DeviceID = {0}", DeviceId);

   try
   {
      ManagementObjectCollection networkAdapters =
         WMIOperation.WMIQuery(strWQuery);
      foreach (ManagementObject networkAdapter in networkAdapters)
      {
         crtNetworkAdapter = networkAdapter;
      }

      crtNetworkAdapter.InvokeMethod(strOperation, null);

      Thread.Sleep(500);
      while (GetNetEnabled() != ((strOperation.Trim() == "Enable")
                                    ? (int)EnumNetEnabledStatus.Enabled
                                    : (int)EnumNetEnabledStatus.Disabled))
      {
         Thread.Sleep(100);
      }

      resultEnableDisableNetworkAdapter =
         (int)EnumEnableDisableResult.Success;
   }
   catch (NullReferenceException)
   {
      // If there is a NullReferenceException, the result of the enable or  
      // disable network adapter operation will be fail 
      resultEnableDisableNetworkAdapter = (int)EnumEnableDisableResult.Fail;
   }

   crtNetworkAdapter.Dispose();

   return resultEnableDisableNetworkAdapter;
}

【讨论】：