Assembly: System (in system.dll)
Listen causes a connection-oriented Socket to listen for incoming connection attempts. The backlog parameter specifies the number of incoming connections that can be queued for acceptance. To determine the maximum number of connections you can specify, retrieve the MaxConnections value. Listen does not block.
If you receive a SocketException, use the ErrorCode property to obtain the specific error code. After you have obtained this code, refer to the Windows Sockets version 2 API error code documentation in the MSDN library for a detailed description of the error. Use Accept or BeginAccept to accept a connection from the queue.
You must call the Bind method before calling Listen, or Listen will throw a SocketException.
This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing.
The backlog parameter is limited to different values depending on the Operating System. You may specify a higher value, but the backlog will be limited based on the Operating System.
The following code example uses Socket to listen for incoming connections.
// create the socket Socket listenSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); // bind the listening socket to the port IPAddress hostIP = (Dns.Resolve(IPAddress.Any.ToString())).AddressList; IPEndPoint ep = new IPEndPoint(hostIP, port); listenSocket.Bind(ep); // start listening listenSocket.Listen(backlog);
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.