IPGlobalProperties.GetActiveTcpListeners Method ()


Returns endpoint information about the Internet Protocol version 4 (IPv4) and IPv6 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.

Exception Condition

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)


for reading network information. Associated enumeration: Read.

.NET Framework
Available since 2.0
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