[Resolved] Button works once, then stops working.

[Monkz]

I am having issues with my program. It should update every time i click the button, but it runs through perfectly on the first click, after the first click it does nothing.

This is a UDP Program, where the client sends a packet with a sequence number and payload which are separate items in the packet. The server receives the packet, reads the sequence number, and then sends back the next sequence number the client should send.

The client then receives that from the server with the same payload.. And then should change its sequence number to the one it recieved, and send that to the server..

The client works up to where the client updates to the sequence number it receives from the server.. But both show no effect on any clicks after.

Heres my Client Code:

Option Strict Off
Imports System.Net.Sockets
 
Public Class Client
    Dim sequence As UInt64
    Private udp As UdpClient = Nothing
    Private client As UdpClient = Nothing
    Private packetReceived As Boolean = False
    Private endPoint As Net.IPEndPoint = Nothing
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        sequence = 1
        udp = New UdpClient()
        endPoint = New Net.IPEndPoint(Net.IPAddress.Any, 6000)
        client = New UdpClient(endPoint)
        Label1.Text = sequence
 
    End Sub
    Private Sub Form1_Shown(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Shown
        ReceivePackets()
    End Sub
 
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
 
    End Sub
 
    Private Sub ReceivePackets()
        Dim state As New UdpState(client, endPoint)
        client.BeginReceive(New AsyncCallback(AddressOf ReceiveCallback), state)
        While packetReceived = False
            Application.DoEvents()
            System.Threading.Thread.Sleep(100)
        End While
    End Sub
 
    Private Sub ReceiveCallback(ByVal ar As IAsyncResult)
        Dim state As UdpState = DirectCast(ar.AsyncState, UdpState)
        Dim u As UdpClient = state.UdpClient
        Dim e As Net.IPEndPoint = state.EndPoint
        Dim receiveBytes As Byte() = u.EndReceive(ar, e)
        Dim strem As New IO.MemoryStream(receiveBytes)
        Dim bf As New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter()
        Dim obj As Object = bf.Deserialize(strem)
        Dim pak As Packet = DirectCast(obj, Packet)
        'Display the packet on UI
        ShowPacketData(pak)
        packetReceived = True
    End Sub
 
    Private Delegate Sub ShowPacketDataCallback(ByVal pak As Packet)
    Private Sub ShowPacketData(ByVal pak As Packet)
 
        If Me.InvokeRequired Then
            sequence = pak.Sequence
            Me.Invoke(New ShowPacketDataCallback(AddressOf ShowPacketData), pak)
        Else
            TextBox1.Text = ("Server Received Sequence: " & pak.Sequence.ToString - 1)
            For Each b As Byte In pak.Payload
                TextBox2.Text &= b.ToString & " "
                Label1.Text = sequence
            Next
        End If
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
 
        Dim payload As Byte() = New Byte() {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, _
                             11, 12, 13, 14, 15, 16, 17, 18, 19, 20, _
                             21, 22, 23, 24, 25, 26, 27, 28, 29, 30, _
                             31, 32, 33}
        Dim pak As New Packet(sequence, payload)
        Dim strem As New IO.MemoryStream()
        Dim bf As New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter()
        bf.Serialize(strem, pak)
        Dim stremByte() As Byte = strem.ToArray()
        udp.Connect("127.0.0.1", 5000)
        udp.Send(stremByte, stremByte.Length)
        strem.Close()
    End Sub
End Class

Heres my Server Code:

Option Strict Off
Imports System.Net.Sockets
 
Public Class Server
    Private client As UdpClient = Nothing
    Private packetReceived As Boolean = False
    Private endPoint As Net.IPEndPoint = Nothing
    Dim sequence As UInt64
    Private packetloss As Int64
    Private udp As UdpClient = Nothing
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        sequence = 1
        packetloss = 0
        endPoint = New Net.IPEndPoint(Net.IPAddress.Any, 5000)
        client = New UdpClient(endPoint)
        udp = New UdpClient()
        Label1.Text = sequence
    End Sub
 
    Private Sub Form1_Shown(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Shown
        ReceivePackets()
    End Sub
 
    Private Sub ReceivePackets()
        Dim state As New UdpState(client, endPoint)
        client.BeginReceive(New AsyncCallback(AddressOf ReceiveCallback), state)
        While packetReceived = False
            Application.DoEvents()
            System.Threading.Thread.Sleep(100)
        End While
    End Sub
 
    Private Sub ReceiveCallback(ByVal ar As IAsyncResult)
        Dim state As UdpState = DirectCast(ar.AsyncState, UdpState)
        Dim u As UdpClient = state.UdpClient
        Dim e As Net.IPEndPoint = state.EndPoint
        Dim receiveBytes As Byte() = u.EndReceive(ar, e)
        Dim strem As New IO.MemoryStream(receiveBytes)
        Dim bf As New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter()
        Dim obj As Object = bf.Deserialize(strem)
        Dim pak As Packet = DirectCast(obj, Packet)
        'Display the packet on UI
        ShowPacketData(pak)
        packetReceived = True
    End Sub
 
    Private Delegate Sub ShowPacketDataCallback(ByVal pak As Packet)
    Private Sub ShowPacketData(ByVal pak As Packet)
 
        If sequence = pak.Sequence Then
            sequence += 1
        Else
            packetloss += 1
        End If
 
 
        If Me.InvokeRequired Then
            Me.Invoke(New ShowPacketDataCallback(AddressOf ShowPacketData), pak)
        Else
            TextBox1.Text = pak.Sequence.ToString
            Label1.Text = sequence
            For Each b As Byte In pak.Payload
                TextBox2.Text &= b.ToString & " "
            Next
        End If
 
        Acknowledge()
 
    End Sub
 
    Private Sub Acknowledge()
 
        Dim payload2 As Byte() = New Byte() {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, _
                                            11, 12, 13, 14, 15, 16, 17, 18, 19, 20, _
                                            21, 22, 23, 24, 25, 26, 27, 28, 29, 30, _
                                            31, 32, 33}
        Dim pak As New Packet(sequence, payload2)
        Dim strem As New IO.MemoryStream()
        Dim bf As New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter()
        bf.Serialize(strem, pak)
        Dim stremByte() As Byte = strem.ToArray()
        udp.Connect("127.0.0.1", 6000)
        udp.Send(stremByte, stremByte.Length)
        strem.Close()
 
    End Sub
End Class