I have a TCP Socket Client (using the Socket Class) that is connected to a simple TCP socket server (just for testing)I have this code snippet :
Dim aSocket as Socket
While aSocket.Connected = True
byteRead = aSocket.Receive(dataByte) 'number of bytes
[code].....
I am facing problem in asynchronous socket communication.
1)I wanted to perform connect(from client to server) operation on enter button and send the data whatever client want to send and disconnect from server. And again client should get connect to server whenever client wanted to send data. this is the mechanism.
i.e how to reuse the socket.
2)Again Server should able to send the data to client.
I wrote a Socket Client which will send the Socket Server some data and get some response from Server. This process will be running once in every 2 seconds.
Now what I need to know is How we can identify the connection lost between Server and Client?
I need this to be implemented in the Client side. If there is no connection then Client should automatically close the connection. Once the connection with the server is available in the next attempt it should connect automatically.
Below is my code, but when i send the message thru client socket i receive Specified argument was out of the range of valid values. Parameter name: size
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim serverStream As NetworkStream = clientSocket.GetStream()
Dim outStream As Byte() = _
System.Text.Encoding.ASCII.GetBytes("0800822000000000000004000000000000000920092126012345001")
[CODE]...
I made a simple TCP server (I've found the example on the web) in VB to receive data from about 40 TCP clients.The clients are not synchronized but sends data about every 18 minutes; the problem is sometimes several clients sends data at the same moment, so I can't receive data.I also made a second program that reads the data (server program writes data on a file, read from the second program) scheduled.
My question is this: I've seen on the web examples about Multithreaded Server Socket Program, so I suppose this could manage my 40 clients (but now the clients are syncronized and send data at the same time in client mode) or is better get data (I have a central client that asks data to all 40 devices in server mode)?
Second question: can I make a single program where I run both TCP client and TCP server at the same time?
how to access client side activity i.e. which client is connected and which computer connected at the same time from server.
View 1 RepliesFor almost a week I am reading and trying to find a solution for checking connection state using a TCP Client (using socket class) In my scenario I have a TCP Client that is connected to a server (it is not controlled by me) and i want that from time to time to check the connection state, and reconnect if necessary.I have read a lot of information on the internet but i did not find a suitable solution.Briefly, these are the methods that i have found on the internet and try to implement.But unfortunatelly, i have found some scenarios where the TCP Server is closed and the TCP Client is still saying Connected 1.Example from MSDN
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I want both the client and server to write and read resp. at a constant rate (which can be configured on the GUI of the client) to the buffer.I am able to send from the client at 150 bytes per packet Now, I should be able to read also at 150 bytes per packet on the server too Since, both are connected through a socket, can we retrieve the socket params (set on the client size, like 150 here) from the server end, using the tcpServer object.Or is it must to send an initial setup packet which tells about these client params and so accordingly the server can continue?
View 1 RepliesI am Working on Teghax Component.Using This Component we want to find out Block title attribute of dwg file in a client server socket application.
1> We get Block title attributes properly of dwg file in windows application form using the getattribute function().
2> We get Block title Attributes properly in that way:-We take a class library where we take a class.in this class we use getattribute function().Then We access the particular class from another project
But when we use the same class(Keep same structure) in client server socket program.Then it gives an exception.i.e ,"Spaicfied cast is not valid"I am Not getting any reply form teghax developer..I attached exception screen sort.Give me Suggestion How to solve this Exception
Code given Bellow :
Public Function Get_DwgFileAttribute(ByVal Sender As ClsTcpConnection, ByVal msgTag As Byte, ByVal message As String) As String
Dictionary = GetHashtable(message)
Dim varfilepath As String = CStr(Dictionary.Item("filePath"))
[code]....
I am working on a chat client and server, and so far it works well, but when I close the client, the server throws an exception because it continues to try to do processes on the disconnected client. I have tried adding clientSocket.Close() in various places throughout the client and server with no luck. Does someone know how to add the disconnect code to either the server or client with this code?Server:
Imports System.Net.Sockets
Imports System.Text
Module Module1
[code].....
Hey guys, I am trying to send data from client to server (encrypted) and the string sent from the client is not the same as recieved from the server. I've been killing my brain for hours to get this to work but I cant manage. Im converting everything to Base64 string.
Client:
Public Sub SendMessage(ByVal msg As String)
Try
SyncLock myclient.GetStream
sw = New IO.StreamWriter(myclient.GetStream)
[code]....
So I have set up a basic client/server connection and I am trying to send a message to one another on connection, I got the client to receive the message from the server, but the server doesn't recieve the clients message. Here is my current code for reading the sent data from the client:
ServerThread.socket = new ServerSocket(5556);
Socket client = ServerThread.socket.accept();
DataInputStream in = new DataInputStream
[code]....
Please excuse my choice of wording and/or mixup of terms, I am a dummy when it comes to socket programming. I am trying to connect to a TCP server, write a message and process a response. I use the following code:
Dim tcpClient As Sockets.TcpClient = New TcpClient()
tcpClient.Connect(hostname, 9080)
Dim networkStream As NetworkStream = tcpClient.GetStream()
[code].....
I am reading data from a socket (as bytes) and storing this data in a string. Then later i need to access specific bytes within the string and do some math with them. However the bytes that I read back from the string are not what I am expecting.
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I have created a Client that can send and receive data via TCP sockets. The objects stored on the serverside are the *exact* same object used for the client. They use the same send and receive protocols.
Now, when i send a string from the server to the client , it does precisely what it should do. However when I send a string to the server.... I do receive the string as an equal length of NULL characters. I run the server and client locally.
Basicly what can influence the behaviour between two completely identical objects performing the exact same task? I wonder if there is some socketflag issue if the TCPlistener.accept function returns a completely different setup then the one I R used to.
(if it is of any interest, the send protocol is asynchronious)
I have been struggling to find a solution for this problem. What I need to do is build a server application that accepts tcp client requests from different clients running on same port say:1003. I experimented by using asynchronous mode call backs etc. but it disconnects once connection is established and does not respond for further requests from the same client.
View 1 Replieshow to create a client/server... But I couldn't... I don't want anything fancy. Just want the client to send the server 4 numbers, depending on the user's choice; after that, the server would turn off the pc, restart it, etc. It all depends on the number received. Is there a rather "simple" way to do it? If it's not to much trouble you could use Atheist's example. (Btw I don't understand the code and, yes, I've checked on [URL])
View 9 RepliesI have a small program which is a tcp client. I send a string from this client to a device over ethernet (it acts as the tcp server). As soon as the device recieves the input string it will respond back with response data. My problem is i am not getting the entire response data back from the server. (device).
Dim serverStream As NetworkStream = clientSocket2.GetStream()
Dim outStream As Byte() = System.Text.Encoding.ASCII.GetBytes("my-cmd")
serverStream.Write(outStream, 0, outStream.Length)
[code]....
We are creating a Who wants to be a millionaire style game in VB. Our server is pulling information such as questions and answers from a Access Database and sending them to the contestants (Clients). All transfer of information is directly from the server to each client. One of the "Life Lines" we want to use is "Ask a friend", where one client is able to Instant message another client for a short time to get help on the question.
[Code]...
i'm using socket programming in vb.net 2005 and make a Server/Client windows application and it used in the network to multi user chat server and havent error and it work , but one BUG in server app : the Server app. work currently until the number of clients more than 30 and then it crashed . and error is "socket.exception" . now tell me what to do ??? it's very very important to me because the number of server's CRASH in on day more than 10 time and i end it and then run again and it's not good for my job .
View 5 RepliesCan you compress data being sent from client to server and etc? If so how would i do this?
View 2 Repliesi am creating a software that needs to transfer data between client and server. i m storing the data in client in a database. but how does server access every clients data.
View 9 RepliesI have a Linq query on the server side of a Silverlight 4 Ria project that returns a number of distinct items based on a time period(Month).The problem I am getting is when the client callback fires the data has been corrupted and all the items returned from the server are duplicates of the last item in the collection.
Server Call
Public Function GetBusinessHeadCountHistory(ByVal businessUnit As String) As IEnumerable(Of EngineeringHeadCountBusinessHistory)
Return From t In ObjectContext.tblTimes
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I have programmed a chat application in VB but as soon as I send any data from a client the server will send it to all. It should send a reply only to a particular client. This is the function I have used.
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I've been working on this project for about a year now. It's a basic clientserver chat program. After a long time of improvement, I decided to test out the strength of my server.
On the client, I fired off 200 chat messages ("FLOOD# 1"... "FLOOD# 200") to the server as fast as possible. The result: Server immediately crashes. After some slight tampering, I was able to get the server to process 135 of the 200 messages before giving up. It no longer crashes, but something different happens. The data from the client is received in order, but when I pass that message to a function (myForm.OnLineReceived), The data is completely out of order. If I add a slight delay between the calling of the OnLineRecieved function, The messages are in perfect order.
Each message from the client is first encrypted, then encoded in base64. An "-" is appended to the end so that the server can easily find the end of each data "packet".
Server Code:
Imports System.Net.Sockets
Imports System.Text
' The UserConnection class encapsulates the functionality of a TcpClient connection
' with streaming for a single user.
[Code].....
basically i just want client to say "C: emp" ENTER
then, server must reply with all its files in c: emp
The problem I have is: When I click on cmdListen in the server form and cmdConnect in the client form,both programs won't respond and they crash for some reason I don't know.
Client source code:
Code:
Imports System.Net.Sockets
Imports System.Text
Public Class Form1
[CODE]...
Code:
Imports System.Net.Sockets
Imports System.Text
Public Class Form1
[CODE]...
I need to encrypt some basic data being sent from server to client.
I was going to open a file in bytes, convert it to chrs (Modify odd numbers by adding 2 and even numbers by adding 3) then use Base 32 (Triacontakaidecimal) or Base 16 (although base 16 will occupy twice the space). Convert the data back to bytes and after do the same with the decryptor.
About using base 32, is there some sort of class in vb.net or maybe an api?
For example, i installed the windows application in more than one pc. All the pc's are in network. I want to save the data in a single database. How it is possible?
View 7 RepliesI developed a simple examination system with registration forms. I used VB.Net as the programming language. I haven't tried manual coding for my problem yet.Anyway this is a project for the company from which I am an intern. The plan is to get every client pc to have this examination/registration application and this application will send the personal info and the score to a central database(server pc).I used MySql as the dbms and developed the application on the same machine which means that the Database server I used is only on the local host.
Now I was about to try to implement the application to one client pc(as a beta test) and installed the necessary files(.net framework) and I also installed MySQL Server(and workbench) in the server pc.When I run the application in the client PC it didn't detect/connect to the ServerPC's MySQL server instance and therefore was not able to record the dummy values I input in the client application. Take note I changed the connection string of my app to point to the ip address of the serverPC.
Should I install the MySQL Server(and Workbench) to every ClientPC so that I can create a server instance that uses the REMOTE HOST option and configure it such that it will connect to the SERVERPC's Database?How should I setup the server so it gives access to the application I installed in all clientPCs?
