Programmatically Enable / Disable Connection

You can achieve this in C# by leveraging WMI and the Win32_NetworkAdapter WMI class. The Win32_NetworkAdapter class has Enable and Disable methods which can be executed on a selected network interface.

An example of usage can be found here:

http://blog.opennetcf.com/ncowburn/2008/06/24/HOWTODisableEnableNetworkConnectionsProgrammaticallyUnderVista.aspx

link not available, but archived at:

http://web.archive.org/web/20120615012706/http://blog.opennetcf.com/ncowburn/2008/06/24/HOWTODisableEnableNetworkConnectionsProgrammaticallyUnderVista.aspx

Briefly, steps to do this are:

1. Generate a wrapper for the class from VS command prompt

   mgmtclassgen Win32_NetworkAdapter /L CS -p NetworkAdapter.cs

2. Stepping through the adapters:

   SelectQuery query = new SelectQuery("Win32_NetworkAdapter", "NetConnectionStatus=2");
   ManagementObjectSearcher search = new ManagementObjectSearcher(query);
   foreach(ManagementObject result in search.Get()) {
    NetworkAdapter adapter = new NetworkAdapter(result);
    // Identify the adapter you wish to disable here. 
    // In particular, check the AdapterType and 
    // Description properties.
    // Here, we're selecting the LAN adapters.
    if (adapter.AdapterType.Contains("Ethernet 802.3")) {
       adapter.Disable();
    }
   }