I posted this code in another thread as an example of how to listen for connecting clients using TcpListener.it is a small part of a larger project, its all my own work,
Imports System.Net
Imports System.Net.Sockets
Public Class Server[code].....
How can I ask my tcpListener to listen to particular IP on specific port? I want my tcpListener to listen to the local IP of the machine. I can get the ipaddress of the pc using Dns.GetHostAddresses(). But, if pc have multiple ip's how can I know which ip address is correct? From tcpClient class I am connecting to the server. So, I know the server ip and so I want to specify ipaddress to my tcpListener class to listen on.
View 1 RepliesI have been programming a TcpListener Program and I have everything working right! So far... Except that when I have multiple clients connecting to my Server... I used a try catch statement to catch the error and it says that tcplistener doesn't allow multi connections... think creating a new thread for each connection sounds like the most reasonible answer but I can't grasp the concept of it...
Here is my frmMain:
Imports System.IO
Imports System.Net
[code].....
I created application database by vb.net and sql server 2005 now I have some computer on the one of them I installed sqlserver 2005 and other (Clients) computers I installed Application how I can connecting my application to sql server on the pc1 or how I can using connection string.
View 2 RepliesI have this code to connect to my server:
client = New TcpClient(txtIP.Text, txtPort.Text)
client.GetStream.BeginRead(readBuffer, 0, BYTES_TO_READ, AddressOf DoRead, Nothing)
SendMessage("/CONNECT|" & Label25.Text)
How do I check if the TcpListener is available?
I am creating an application that will be talking over the LAN (and eventually, WAN) which uses the Tcplistener and Tcpclient objects.Now, I have this working absolutely fine locally using the loopack address although when I change the IP of the listener to 0.0.0.0 (listening for all IPs) and the IP in the client application, to the IP of the server, it throws an exception when connecting. The client says something along the lines of the the server has rejected the incoming connection. So i disabled all firewalls temporarily but I still have the problem.I have ran netstat on the server which clearly shows that it is listening for an incoming connection on 0.0.0.0. [code]
View 5 RepliesI have this code to connect to my server:
client = New TcpClient(txtIP.Text, txtPort.Text)
client.GetStream.BeginRead(readBuffer, 0, BYTES_TO_READ, AddressOf DoRead, Nothing)
SendMessage("/CONNECT|" & Label25.Text)
[code].....
How do I free an instance of TcpListener?
How, in VisualBasic, to I delete something from a 'new'?[code]...
I have an application that listens for connections asynchronously. When a connection comes in, it spawns a new thread from the callback method. This works fine for up to about 13 simultaneous connections then it dies with an out of memory error. The threads that are spawned just do a CHAP handshake and authenticate then go in to a command loop where they sleep until a command comes in or a timeout occurs. I have pasted the code below. Sometimes it will not throw an error but the thread never gets spawned although the connection is accepted.
Code:
Imports System.Net.Sockets
Imports System.Threading
Public Class UpdateMonitor
[Code]....
I have just created a website server with Visual Basic 2008. I want my server to have the famous "resume donwload" function... but i dont know how the HTMLHeader should look like when its resuming a download.
Here is how the header normaly looks:
HTMLHeader = _
"HTTP/1.0 200 OK" & ControlChars.CrLf & _
"Server: Website Server " & My.Application.Info.Version.ToString & ControlChars.CrLf & _
"Content-Length: " & GetFileSize & ControlChars.CrLf & _
"Content-Type: " & GetContentType(StringRequest) & _
ControlChars.CrLf & ControlChars.CrLf
I am trying to make a TCP chat program, but instead of having people enter in the ip of the computer they wish to talk to everytime, i would like the program to be able to listen on all ip addresses, so that it will provide for a better user experience, and that i can have chat rooms with multiple people joining. I have the code working with entering in ips, however, when i use the IPAddress.any command it will not send messages.
View 3 RepliesHow can I detect when a client disconnects from the TcpListener ?
Each of my clients is handled in a separate thread.
Is it necessary to close the connection of a tcplistener or tcpclient after every message received, or is it possible to close it at a later time while it continues to receive data? Is there any major security issue with leaving it open and listening? I know trojans tend to open a listener and leave it open, will my program be detected as such? Its just a simple chat program....
View 1 Replies[code]I send the Thread via Thread.Sleep to sleep mode when nothing happens here. Does this affect the TCPListener in his work somehow and what happens to an incomming connection while the Thread is in sleep-mode?
View 3 RepliesI am creating a simple program. (soon to be vastly complex) that is connecting to a server, and sending an authentication code to connect. I got the connection part, but what keeps breaking up is the method of authenticating. I have the entire authentication process in a while loop, so that it will keep going until it receives the authentication reply from the server (an OK-002938, or what ever client number the server decides.
This is my client code for the event:
Private Sub CONNECTSERVER_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles CONNECTSERVER.DoWork
Try
If network_client.Connected = False Then
network_client.Client.Connect(My.Settings.service_address.ToString, My.Settings.service_port.ToString)
[Code] .....
The client side is flawless. But the server side, works, but it doesn't continue past storing the bytes into a container...
I have a class that inherits from the TcpListener, this class Shadows the Start method just to call the base Start() and the base BeginAccept Tcp Client(). From time to time the method is called but the port is not opened (netstat does not show the port open).[code]The class that uses the ExtendedTcpListener implements the IDisposable pattern and inside the Dispose the ExtendedTcpListener.Stop is called.The stop text is not present at the logs when the problems happens.
View 4 RepliesI am working on a remote administration tool. But I have a problem, since the server connects to the client the client needs a tcplistener. But when the client starts too listen the program freezes and I can't do anything. The reason is that the tcplistener runs in a loop which freezes the form. What shall I do too fix the program?
View 1 RepliesBasically, in my Tcp Library I'm working on, whenever the system is told to "Stop", the OnClientConnected() Routine fires off, which is only raised under two circumstances: When a Client connects (obviously) When the server is told to shutdown
Now, the first one is handled just fine. But the second one is not. In fact, it has caused me a great deal of headache because it keeps throwing exceptions on this line in particular:
Dim _tcpClient As System.Net.Sockets.TcpClient = _tcpListener.EndAcceptTcpClient(IR)
When I hover over while debugging, I can see a few members that reveal exception data I could utilize; but unfortunately those members are private and I don't want to utilize reflection unless I have to since it could slow down performance where there may not be a real reason to.
I have thought of writing in a Boolean check to see if the server received a shutdown signal and that would indicate that it's time to not accept anything, but I want to avoid that if possible.
Is there any way to see if the TcpListener is no longer accepting connections and has had .Stop() called without reverting to catching the ObjectDisposedException that is raised? (because the Socket that is "accepted" is actually a disposed one)
I found the code linked below on on of Microsoft's websites for listening for keypresses, however I can't seem to ge thte code to respond?
View 5 RepliesThis is my first post, so hopefully I'm asking it in the correct place.
Currently I have two subs where the first calls the second.
Sub Sub1()
'some code
Call Sub2(x)
End Sub
Sub Sub2()
'some code
End Sub
This means that Sub1 does not end until after Sub2 is complete.I need to have Sub2 run after Sub1 has ended. In my case Sub1 is triggered from an application event, so calling the two subs from another 'parent' sub would not work.Is there a way that I can listen for the 'End Sub Event' of a sub?I am currently working in VBA but will be heading to .net shortly so I'll take whatever flavour of code people can help with.
I have a program running on a machine on the local network that serves data on port 23. I'd like to be able to listen for data on this port, and add the data to a listbox when and if it comes in. Idealy this would run async. I sort of gotten this to work using the following: [code]
View 6 RepliesI have barcode reader work by rs232 , i using converter from rs232 to TCP/IP to make it connect by TCP/IP, Now barcode send data on this Ip "192.168.0.125" on local network and the IP port is 50000 How i can listen to this ip to read the data send to this ip?
View 8 RepliesI am developing an Application that uses TCP To listen for connections, and then when a message is sent to the server and then it alerts the IP that is running the server. (Lets say the server is on a iPhone, and some how the iPhone gets a text message, which alerts a tcp server running in the background via a .jar, it would send the owner of the iPhone a message on the computer telling it it has a text. This is just an example though, but I think it gets the general idea across. I've been trying to do this, and I can connect to a TCP Server (using 127.0.0.1:8888 for testing purposes, will move to a solid IP and Port later). I can start the server (its still buggy and under development) but i don't know how to connect to the server via an application, and when a certain message is received to alert the IP Running the server.
My Server Code is:
Dim serverSocket As New TcpListener(8888)
Dim clientSocket As TcpClient
Dim infiniteCounter As Integer
Dim counter As Integer
serverSocket.Start()
[Code] .....
Now I know that to connect you'd do something like
Code:
Dim clientSocket As New System.Net.Sockets.TcpClient()
Dim serverStream As NetworkStream
clientSocket.Connect("127.0.0.1", 8888)
serverStream = clientSocket.GetStream()
And I know I would have to use some sort of Byte() method to send/receive messages, but I am at a loss on how to set it all up.
I got 11 errors in my VB program. All the errors look similar: X is ambiguous in the namespace Y
Error line: Imports System.Net.Sockets
Imports System.Text
Module Module1
Sub Main()
Dim serverSocket As New TcpListener(System.Net.IPAddress.Parse("192.168.1.100"), 8888)
Is that possible to create our own server using TcpListener class with IIS being uninstalled?
View 2 RepliesIt seems the most obvious thing, but I just can't work out how to get the length of bytes sent over a network using a TCPClient and TCPListener? This is my code so far:
'Must listen on correct port- must be same as port client wants to connect on.
Const portNumber As Integer = 9999
Dim tcpListener As New TcpListener(IPAddress.Parse("192.168.2.7"), portNumber)
[Code]...
I need to get the length of the networkstream to set the size of the array of bytes I'm going to read the data into. But the networkStream.length is unsupported and does not work and throws an Notsupportedexception.
The only other way I can think of is to send the size of the data before sending the data, but this seems the long way round.
I am trying to build a sort of basic server thing and I cannot seem to get the thing to work properly. I have a client and a server. The client sends a string, the server receives then replies. I cannot get the server to continue responding.
It works in one direction Client -> Server
But because the server is continuously listening the form becomes not responding, thus I cannot send messages from the server. Although it says that its not responding I know that it is just using all of the processing for listening because when I send something from the client the server responds, just the form is stuck because of the listener.
I have a background thread that sits waiting for new clients to connect to my TcpListener and when a new client connects it passes it off onto another worker thread and then loops straight back to waiting for another client. Like so:
[Code]...
Obviously I could just handle the exception and ignore it but I'm sure there must be a more proper way of doing it. One thing I am thinking of trying is using the BeginAcceptTcpClient and EndAcceptTcpClient methods but for one thing I'm not sure if that will actually help and for another thing the Begin and End versions of methods have always confused me in the past... I mean for a start how do you know when to call End?
I figured this must be a fairly common problem but searching the forum only turned up one result and it wasnt any use. I'll keep playing around and trawling google but just wondered if anyone had come across this before?
i made a simple tcp listener server.Now I can use my client to connect,it connets, everything is good. The
problem is when I open the first client, then I open another one, it doesn't connect. It accepts only 1.Any way I can accept multi connections?
[Code]...
I've a plugin which always listening to the port 6002, and i have an ASP.net application which sending messages to the same port and receiving the reply from the plugin on the same port,Sending is working fine, and the plugin sends a reply on the same port but i don't know how to catch this reply, when i try to listen to the same port using Tcplistener the start method throws this exception : Only one usage of each socket address (protocol/network address/port) is normally permitted,
View 4 Replies