IPGlobalProperties.GetActiveTcpListeners Method

Definition

Namespace:

System.Net.NetworkInformation

Assembly:

System.Net.NetworkInformation.dll

Source:

IPGlobalProperties.cs

Returns endpoint information about the Internet Protocol version 4 (IPv4) and IPv6 Transmission Control Protocol (TCP) listeners on the local computer.

public:
 abstract cli::array <System::Net::IPEndPoint ^> ^ GetActiveTcpListeners();

[System.Runtime.Versioning.UnsupportedOSPlatform("android")]
public abstract System.Net.IPEndPoint[] GetActiveTcpListeners ();

[<System.Runtime.Versioning.UnsupportedOSPlatform("android")>]
abstract member GetActiveTcpListeners : unit -> System.Net.IPEndPoint[]

Public MustOverride Function GetActiveTcpListeners () As IPEndPoint()

Returns

IPEndPoint[]

A IPEndPoint array that contains objects that describe the active TCP listeners, or an empty array, if no active TCP listeners are detected.

Attributes

UnsupportedOSPlatformAttribute

Exceptions

NetworkInformationException

The Win32 function GetTcpTable failed.

Examples

The following code example displays endpoint information for active TCP listeners.

void ShowActiveTcpListeners()
{
   Console::WriteLine( "Active TCP Listeners" );
   IPGlobalProperties ^ properties = IPGlobalProperties::GetIPGlobalProperties();
   array<IPEndPoint^>^endPoints = properties->GetActiveTcpListeners();
   System::Collections::IEnumerator^ myEnum7 = endPoints->GetEnumerator();
   while ( myEnum7->MoveNext() )
   {
      IPEndPoint^ e = safe_cast<IPEndPoint^>(myEnum7->Current);
      Console::WriteLine( e );
   }
}

public static void ShowActiveTcpListeners()
{
    Console.WriteLine("Active TCP Listeners");
    IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
    IPEndPoint[] endPoints =  properties.GetActiveTcpListeners();
    foreach (IPEndPoint e in endPoints)
    {
        Console.WriteLine(e.ToString());
    }
}

Remarks

The objects returned by this method include listeners in all TCP states except the Listen state.

The TCP protocol is defined in IETF RFC 793. Note that the objects returned by this method reflect the connections as of the time the array is created. This information is not updated dynamically.