Socket.Listen questions

[Imperceptus]

For the life of me I tried googling and have come up with much.  I am trying to add a listen functionality to my socket class. I figured making it roughly the same way as I made the connect methods would be a good idea. Heres what I have.

Code Select Expand

   Public Sub Listen()
        Try
            _Socket = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
            _Socket.Listen(1)
            _Socket.BeginAccept(AddressOf ConnectionRequest, Nothing)
        Catch ex As Exception
            RaiseEvent SocketError(ex)
        End Try
    End Sub
    Private Sub ConnectionRequest()
        _Socket.Accept()
        _Socket.BeginReceive(_Buffer, SocketFlags.None, AddressOf DataFromRemoteClient, Nothing)
    End Sub
    Private Sub DataFromRemoteClient()
        _Socket.Receive(_Buffer)
        RaiseEvent DataRecieved(_Buffer.ToString)
    End Sub

Suggestions and related comments welcome.

[Imperceptus]

I have gotten this to work. Changed my code alot in part to code i found at http://www.codeguru.com/Csharp/Csharp/cs_network/sockets/article.php/c7695/

Here is the update segment

Code Select Expand


    Public Sub Listen()
        Dim ipHostInfo = Dns.GetHostEntry(Dns.GetHostName)
        Dim ipAddress = ipHostInfo.AddressList(0)
        _localip = New IPEndPoint(ipAddress.Any, 6112)
        '_Socket =
        _Socket.Bind(_localip)
        _Socket.Listen(100)
        '_Socket.BeginAccept(AddressOf ConnectionRequest, _State)
        _Socket.BeginAccept(New AsyncCallback(AddressOf ConnectionRequest), _Socket)
    End Sub
    Private Sub ConnectionRequest(ByVal AR As IAsyncResult)
        _Socket = _Socket.EndAccept(AR)
        RaiseEvent ConnectedUI("Client Connected!")
        _Socket.BeginReceive(_Buffer, 0, _
                             _Buffer.Length, _
                             SocketFlags.None, _
                             AddressOf DataFromRemoteClient, _
                             _Socket)
    End Sub
    Private Sub DataFromRemoteClient(ByVal AR As IAsyncResult)
        Dim IRx As Integer = _Socket.EndReceive(AR)
        Dim data As System.Text.Decoder = System.Text.Encoding.UTF8.GetDecoder
        Dim chars As Char() = New Char(IRx) {}
        Dim d As System.Text.Decoder = System.Text.Encoding.UTF8.GetDecoder()
        Dim charLen As Integer = d.GetChars(_Buffer, 0, IRx, chars, 0)
        Dim szData As New String(chars)
        If charLen = 0 Then RaiseEvent DisconnectedUI("Connection Lost")
        RaiseEvent DataRecieved(szData)
        ' RaiseEvent DataRecieved(_Buffer.ToString)
    End Sub


Trying to figure out how to catch when the client disconnects now, lol.

[Warrior]

Usually Sockets raise a SocketException when they send data once they're disconnected -- as well as bytesRead from your Recv() will be zero.

[Imperceptus]

Will look into that. thanks.

[Imperceptus]

your thoughts did lead me to detecting the closing of the connection.  unfortunate that until I fix my threading error this problem does me little good,lol.