Sending an receiving two types of data across TCP connection - vb.net

Question

On the Client I want to -
I want to send a screenimage from the client and receive a string with cursor coordinates in.
On the server I want to receive and display the screenimage on Form2
and then send back my cursor coordinates to the client.
I can successfully send text messages from the client and receive them on the server using this code -
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
senddata("CHAT|" & TextBox3.Text) 'send the data with CHAT| as header
TextBox4.Text &= "You: " & " " & TextBox3.Text.Split("|")(0) & vbNewLine
End Sub
Sub senddata(ByVal message As String)
Dim sw As New StreamWriter(t.GetStream) 'declare a new streamwriter
sw.WriteLine(message) 'write the message
sw.Flush()
End Sub
and receive it on the server with this code -
Imports System.IO
Imports System.Net.Sockets
Public Class ConnectedClient
Private cli As TcpClient 'decleare a tcp client which will be the client that we assign to an instance of this class
Private uniqueid As String 'this will be used for the name property
Public Property name ''This will be the name of the ID containing its Unique ID
Get
Return uniqueid 'when we want to get it, it will return the Unique ID
End Get
Set(ByVal value)
uniqueid = value 'Used for setting the name
End Set
End Property
Sub New(ByVal client As TcpClient)
Dim r As New Random 'create a new random to serve as way to create our unique ID
Dim x As String = String.Empty 'declare a new variable to hold the ID
For i = 0 To 7 'we are goign to have an ID of 7 randomly generated characters
x &= Chr(r.Next(65, 89)) 'create a generate dnumber between 65 and 89 and get the letter that has the same ascii value (A-Z)
' and add it onto the ID string
Next
Me.name = client.Client.RemoteEndPoint.ToString().Remove(client.Client.RemoteEndPoint.ToString().LastIndexOf(":")) & " - " & x 'set the name to the Unique ID
cli = client 'assign the client specified to the TCP client variable to we can operate with it
cli.GetStream.BeginRead(New Byte() {0}, 0, 0, AddressOf read, Nothing) 'start reading using the read subroutine
End Sub
Public Event gotmessage(ByVal message As String, ByVal client As ConnectedClient) 'this is raised when we get a message from the client
Public Event disconnected(ByVal client As ConnectedClient) 'this is raised when we get the client disconnects
Sub read(ByVal ar As IAsyncResult) 'this will process all messages being recieved
Try
Dim sr As New StreamReader(cli.GetStream) 'initialize a new streamreader which will read from the client's stream
Dim msg As String = sr.ReadLine() 'create a new variable which will be used to hold the message being read
RaiseEvent gotmessage(msg, Me) 'tell the server a message has been recieved. Me is passed as an argument which represents
' the current client which it has recieved the message from to perform any client specific
' tasks if needed
cli.GetStream.BeginRead(New Byte() {0}, 0, 0, AddressOf read, Nothing) 'continue reading from the stream
Catch ex As Exception
Try 'if an error occurs in the reading purpose, we will try to read again to see if we still can read
Dim sr As New StreamReader(cli.GetStream) 'initialize a new streamreader which will read from the client's stream
Dim msg As String = sr.ReadLine() 'create a new variable which will be used to hold the message being read
RaiseEvent gotmessage(msg, Me) 'tell the server a message has been recieved. Me is passed as an argument which represents
' the current client which it has recieved the message from to perform any client specific
' tasks if needed
cli.GetStream.BeginRead(New Byte() {0}, 0, 0, AddressOf read, Nothing) 'continue reading from the stream
Catch ' IF WE STILL CANNOT READ
RaiseEvent disconnected(Me) 'WE CAN ASSUME THE CLIENT HAS DISCONNECTED
End Try
End Try
End Sub
Sub senddata(ByVal message As String) 'this is used to deal with sending out messages
Dim sw As New StreamWriter(cli.GetStream) 'declare a new streamwrite to write to the stream between the client and the server
sw.WriteLine(message) 'write the message to the stream
sw.Flush()
End Sub
Sub listen(ByVal port As Integer)
Try
Dim t As New TcpListener(IPAddress.Any, port) 'declare a new tcplistener
t.Start() 'start the listener
Do
Dim client As New ConnectedClient(t.AcceptTcpClient) 'initialize a new connected client
AddHandler client.gotmessage, AddressOf recieved 'add the handler which will raise an event when a message is recieved
AddHandler client.disconnected, AddressOf disconnected 'add the handler which will raise an event when the client disconnects
Loop Until False
Catch
End Try
End Sub
In a totally different application I can successfully send the screen image from the client using this code
Imports System.Net.Sockets
Imports System.Threading
Imports System.Drawing
Imports System.Runtime.Serialization.Formatters.Binary
Public Class Form1
Dim client As New TcpClient
Dim ns As NetworkStream
Dim port As Integer
Dim server As TcpListener
Dim listening As New Thread(AddressOf Listen)
Dim GetImage As New Thread(AddressOf ReceiveCursor)
Private Sub Button1_Click_1(sender As Object, e As EventArgs) Handles btnConnect.Click
port = CInt(txtPort.Text)
Try
If btnConnect.Text = "Connect" Then
client.Connect(txtIP.Text, port)
'MsgBox("Client connected !")
Timer1.Start()
btnConnect.Text = "Disconnect"
Else
btnConnect.Text = "Connect"
Timer1.Stop()
End If
Catch ex As Exception
MsgBox("Failed to connect..." + ex.Message)
End Try
End Sub
Public Function Desktop() As Image
Dim bounds As Rectangle = Nothing
Dim screenshot As System.Drawing.Bitmap = Nothing
Dim graph As Graphics = Nothing
bounds = Screen.PrimaryScreen.Bounds
screenshot = New Bitmap(bounds.Width, bounds.Height, System.Drawing.Imaging.PixelFormat.Format32bppPArgb)
graph = Graphics.FromImage(screenshot)
graph.CopyFromScreen(bounds.X, bounds.Y, 0, 0, bounds.Size, CopyPixelOperation.SourceCopy)
Return screenshot
End Function
Private Sub SendDesktop()
Dim bf As New BinaryFormatter
ns = client.GetStream
bf.Serialize(ns, Desktop())
End Sub
Private Sub BtnShare_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnShare.Click
If btnShare.Text.StartsWith("Share") Then
Timer1.Start()
'port = Integer.Parse(Me.txtPort.Text)
'server = New TcpListener(port)
'listening.Start()
btnShare.Text = "Stop Sharing"
Else
Timer1.Stop()
btnShare.Text = "Share Desktop"
End If
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
SendDesktop()
' SetCursorPosition()
End Sub
Private Sub ReceiveCursor()
Dim bf As New BinaryFormatter
While client.Connected = True
ns = client.GetStream
txtCursorPosition.Text = bf.Deserialize(ns)
End While
End Sub
Private Sub Listen()
While client.Connected = False
server.Start()
client = server.AcceptTcpClient
End While
GetImage.Start()
End Sub
Public Sub StopListening()
GetImage.Abort()
server.Stop()
client = Nothing
If listening.IsAlive Then
listening.Abort()
End If
End Sub
End Class
and receive it on the server using this code -
Imports System.Net.Sockets
Imports System.Threading
Imports System.Drawing
Imports System.Runtime.Serialization.Formatters.Binary
Public Class Form2
Dim port As Integer
Dim client As New TcpClient
Dim ns As NetworkStream
Dim server As TcpListener
Dim listening As New Thread(AddressOf Listen)
Dim GetImage As New Thread(AddressOf ReceiveImage)
Private Sub Form2_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'Start the timer, obtain the port and start listening
Timer1.Start()
port = Integer.Parse(Form1.txtPort.Text)
server = New TcpListener(port)
listening.Start()
End Sub
Private Sub ReceiveImage()
Dim bf As New BinaryFormatter
While client.Connected = True
ns = client.GetStream
PictureBox1.Image = bf.Deserialize(ns)
End While
End Sub
Private Sub Listen()
While client.Connected = False
server.Start()
client = server.AcceptTcpClient
End While
GetImage.Start()
End Sub
Public Sub StopListening()
GetImage.Abort()
server.Stop()
client = Nothing
If listening.IsAlive Then
listening.Abort()
End If
End Sub
End Class
Is there a way of doing both using the same connection and somehow detecting which is text and which is the screenimage?