VB.NET TCP Server/Client - Get IP of connected client - vb.net

Question

I'm trying to get the IP address of the connected client but I don't know what I doing wrong. Where I can find it? I think near Sub AcceptClient. I was trying to convert cClient to string, but it always results to True or False. I'm trying to get the argument ar from cClient, which gives me an empty result.
Client.Client.RemoteEndPoint doesn't work or I can't use it correctly.
Form1.vb from Server project
Imports System.IO, System.Net, System.Net.Sockets
Public Class Form1
Dim Listener As TcpListener
Dim Client As TcpClient
Dim ClientList As New List(Of ChatClient)
Dim sReader As StreamReader
Dim cClient As ChatClient
Sub xLoad() Handles Me.Load
Listener = New TcpListener(IPAddress.Any, 3818)
Timer1.Start()
Listener.Start()
xUpdate("Server Started", False)
Listener.BeginAcceptTcpClient(New AsyncCallback(AddressOf AcceptClient), Listener)
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
''Set view property
ListView1.View = View.Details
ListView1.GridLines = True
ListView1.FullRowSelect = True
'Add column header
ListView1.Columns.Add("Adres IP", 120)
ListView1.Columns.Add("Nazwa użytkownika", 120)
End Sub
Sub AcceptClient(ByVal ar As IAsyncResult)
cClient = New ChatClient(Listener.EndAcceptTcpClient(ar))
AddHandler(cClient.MessageRecieved), AddressOf MessageRecieved
AddHandler(cClient.ClientExited), AddressOf ClientExited
ClientList.Add(cClient)
xUpdate("New Client Joined", True)
Listener.BeginAcceptTcpClient(New AsyncCallback(AddressOf AcceptClient), Listener)
End Sub
Sub MessageRecieved(ByVal Str As String)
xUpdate(Str, True)
End Sub
Sub ClientExited(ByVal Client As ChatClient)
ClientList.Remove(Client)
xUpdate("Client Exited", True)
End Sub
Delegate Sub _xUpdate(ByVal Str As String, ByVal Relay As Boolean)
Sub xUpdate(ByVal Str As String, ByVal Relay As Boolean)
On Error Resume Next
If InvokeRequired Then
Invoke(New _xUpdate(AddressOf xUpdate), Str, Relay)
Else
Dim nStart As Integer
Dim nLast As Integer
If Str.Contains("</>") Then
nStart = InStr(Str, "</></>") + 7
nLast = InStr(Str, "<\><\>")
Str = Mid(Str, nStart, nLast - nStart)
'dzielenie strina po odpowiednim syymbolu na przed i po symbolu :D
Dim mystr As String = Str
Dim cut_at As String = ","
Dim x As Integer = InStr(mystr, cut_at)
Dim string_before As String = mystr.Substring(0, x - 1)
Dim string_after As String = mystr.Substring(x + cut_at.Length - 1)
Dim otherItems As String() = {string_after}
ListView1.Items.Add(string_before).SubItems.AddRange(otherItems) 'use SubItems
ElseIf Str.Contains("<A>") Then
nStart = InStr(Str, "<A>") + 4
nLast = InStr(Str, "<B>")
Str = Mid(Str, nStart, nLast - nStart)
ListBox2.Items.Add(Str & vbNewLine)
Else
TextBox1.AppendText(Str & vbNewLine)
If Relay Then Send(Str & vbNewLine)
End If
End If
End Sub
Private Sub TextBox2_KeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles TextBox2.KeyDown
If e.KeyCode = Keys.Enter Then
e.SuppressKeyPress = True
xUpdate("Server Says: " & TextBox2.Text, True)
TextBox2.Clear()
End If
End Sub
Sub Send(ByVal Str As String)
For i As Integer = 0 To ClientList.Count - 1
Try
ClientList(i).Send(Str)
Catch
ClientList.RemoveAt(i)
End Try
Next
End Sub
End Class
ChatClient.vb from Server project
Imports System.Net.Sockets, System.IO
Public Class ChatClient
Public Event MessageRecieved(ByVal Str As String)
Public Event ClientExited(ByVal Client As ChatClient)
Private sWriter As StreamWriter
Public Client As TcpClient
Sub New(ByVal xclient As TcpClient)
Client = xclient
client.GetStream.BeginRead(New Byte() {0}, 0, 0, AddressOf Read, Nothing)
End Sub
Private Sub Read()
Try
Dim sr As New StreamReader(Client.GetStream)
Dim msg As String = sr.ReadLine()
RaiseEvent MessageRecieved(msg)
Client.GetStream.BeginRead(New Byte() {0}, 0, 0, New AsyncCallback(AddressOf Read), Nothing)
Catch
RaiseEvent ClientExited(Me)
End Try
End Sub
Public Sub Send(ByVal Message As String)
sWriter = New StreamWriter(Client.GetStream)
sWriter.WriteLine(Message)
sWriter.Flush()
End Sub
End Class

Answer 1

You can get the IP address from the underlying socket by converting the Socket.RemoteEndPoint property into an IPEndPoint:
Dim Address As IPAddress = CType(cClient.Client.Client.RemoteEndPoint, IPEndPoint).Address
MessageBox.Show(Address.ToString()) 'Example.