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IPGlobalProperties.GetActiveTcpListeners Method

Returns endpoint information about the Internet Protocol version 4 (IPV4) Transmission Control Protocol (TCP) listeners on the local computer.

Namespace:  System.Net.NetworkInformation
Assembly:  System (in System.dll)

public abstract IPEndPoint[] GetActiveTcpListeners()

Return Value

Type: System.Net.IPEndPoint[]
A IPEndPoint array that contains objects that describe the active TCP listeners, or an empty array, if no active TCP listeners are detected.


The Win32 function GetTcpTable failed.

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.

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

public static void ShowActiveTcpListeners()
    Console.WriteLine("Active TCP Listeners");
    IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
    IPEndPoint[] endPoints =  properties.GetActiveTcpListeners();
    foreach (IPEndPoint e in endPoints)
void ShowActiveTcpListeners()
    Console::WriteLine(S"Active TCP Listeners");
    IPGlobalProperties* properties = IPGlobalProperties::GetIPGlobalProperties();
    IPEndPoint* endPoints[] =  properties->GetActiveTcpListeners();
    System::Collections::IEnumerator* myEnum7 = endPoints->GetEnumerator();
    while (myEnum7->MoveNext())
        IPEndPoint* e = __try_cast<IPEndPoint*>(myEnum7->Current);

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0