.NET VB How to have Server Listen on Multiple Ports?

Question

I'm writing a very small and simple server that I want to listen on multiple ports.

I'm using the below, but connections to port 8081 are not being accepted - any suggestions what I'm doing wrong?

(I actually want to listen on multiple ports, I'm not confusing multiple connections)

Public Sub StartServer()

    Dim ports() As Integer = {8080, 8081}
    Dim portList As String = ""



    Dim address As IPAddress = IPAddress.Any

    ' map the end point with IP Address and Port
    'Create Endpoints
    Dim EndPoints(ports.Length) As IPEndPoint

    'Create sockets
    Dim Sockets(ports.Length) As Socket

    Dim i As Integer = 0
    For i = 0 To ports.Length - 1
        portList = portList & ports(i) & " : "
        EndPoints(i) = New IPEndPoint(address, ports(i))
        Sockets(i) = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
        Sockets(i).Bind(EndPoints(i))
        Sockets(i).Listen(20)

        Log("Listening on: All ips &  Port: " & ports(i))


    Next

    Log("Listening on: All ips &  Ports: " & portList)



    Do While Not Me.DoStop
        ' Wait for an incoming connections
        For i = 0 To ports.Length - 1
            Dim sock As Socket = Sockets(i).Accept()


            ' Connection accepted

            ' Initialise the Server class
            Dim ServerRun As New Server(sock)

            ' Create a new thread to handle the connection
            Dim t As Thread = New Thread(AddressOf ServerRun.HandleConnection)


            t.IsBackground = True
            t.Priority = ThreadPriority.BelowNormal
            t.Start()
        Next

        ' Loop and wait for more connections
    Loop

End Sub

Answer 1

The synchronous method Sockets(i).Accept will block until it receives a connection. The accept method will not be called on your second socket until you have a connection on your first.

I think you want to implement asynchronous sockets, there is a sample at http://msdn.microsoft.com/en-us/library/fx6588te.aspx

Your arrays are also one element too long.

Dim EndPoints(ports.Length - 1) As IPEndPoint