This documentation is archived and is not being maintained.

IPGlobalProperties.GetActiveTcpConnections Method

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

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

public abstract TcpConnectionInformation[] GetActiveTcpConnections ()
public abstract TcpConnectionInformation[] GetActiveTcpConnections ()
public abstract function GetActiveTcpConnections () : TcpConnectionInformation[]
Not applicable.

Return Value

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

Exception typeCondition


The Win32 function GetTcpTable failed.

The objects returned by this method include connections in all TCP states except the Listen state. You can check the state of a connection by calling 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 example displays endpoint information for active TCP connections.

public static void ShowActiveTcpConnections()
           Console.WriteLine("Active TCP Connections");
           IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
           TcpConnectionInformation[] connections = properties.GetActiveTcpConnections(); 
           foreach (TcpConnectionInformation c in connections)
               Console.WriteLine("{0} <==> {1}", 

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

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0