VS 2008 - Sending Data From Client To Server (No Communication)
Oct 13, 2010
I'm not sure what I have done wrong, I am trying to get my program to send data (UsernamesPasswords) from client to server, then the server says if it's right or wrong.
The error is on this line:
Dim networkStream As NetworkStream = TcpClient.GetStream()
Heres the Client:
Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
If TextBox1.Text = "" Then
MsgBox("You must enter UN/PW!")
[Code] .....
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
I have a Client/ server application where the Server is in java and Client is in Vb.net.When i send large string from client to server am not receiving complete text.code attached below.
client-- VB.net- Try Dim clientSocket As New System.Net.Sockets.TcpClient()
I made some code in vb.net which checks if a certain process is running, and returns a 1 if it is, or a 0 if it isn't. Now I want it to send a packet to my server or something which would log the IP of the client, or something similar.
Im doing a little program (.net2) that need to get info from a server.For starters I just want the Client-program to send a "Hi" and receive a"Ok" from server when client-program is started.
I'm doing a small project. It works on a LAN. The working of the project is:In client side, a user would enters "username" and "password". It would sent that to the server, along with the time.The server would authenticates info on checking a db and writes some info to the db.Also, the server should be able to sent some commands or instructions to the clients.These commands on received by the client, it would invoke certain functions/subs on the client based on the command.So, would it be better to use TCP client & listener or WCF ?
I have a client/server program. There is a variable called readData that takes returndata and places it there. My question is, why can't I access this variable directly, for instance, varC = readData and then try to access a piece of it i.e. textbox1.text = varC(2), I get an error "object reference not set to instance of an object". Why is this happening? It is because the readData is a networking 'component'? How do I get around this? I can post more code from the server app if needed.
The client/server communication will only take place in the same network.I can use TCP, but then I have to configure separate IP ports for every server instance. I can however simply use named pipes so I don't have to think about port numbers and simply use the name of the server instance.There will not be very frequent and/or large data client/server communication. It's some sort of a ERP application that will only communicate once per 30 seconds on average.
How would I make a Visual Basic application talk to a web server? Someone will press something on the site and I want the application to display the information that the web site passes along to it.
I have a TCP connection code for client and server communication. It's not meant to be malware but it collects the clients computer information and then connects to the server.
It successfully "connects" but then immediately disconnects.Here is the code for the server:
Dim Listener As TcpListener Dim Client As TcpClient Dim ClientList As New List(Of ChatClient) Dim sReader As StreamReader
[Code]...
I have port forwarding all done and it works if I run the client and server on my own machine. If I run the client on another machine though It gives me a message box saying that it connected with the clients remote IP and at the same time it tells me it disconnected. The client never sends the system information. What is the problem?
I need to control a device with a GPIB port. I have the commands that I need to use to do this; but I don't know which is the sintaxis in Visual Basic.
For example if I need to send a instruction like "START:0.01" to the external device which are the libraries that I have to include?, how should I write the programming line to do this?
The main tasks that I need to program are sending data, receiving data, and saving data
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)
I've been playing around with the TCP client/server sample code I found on [URL] but I can't seem to get it to function correctly. The problem I am having is that if I try to send data from the client a second time I get nothing back, not even an error that it couldn't send data. Every time I run the project it works the first time but that's it. When I was running the code line by line it seems to get to 'networkStream.Read(bytes, 0, CInt(tcpClient.ReceiveBufferSize))' and then it jumps over the rest of the routine.
i want to send multiple screenshot images from my client to server.. now i already get the screenshot code.. and the only problem i have is that .. i can't send them in my server..
how 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])
I am new to VB.net and struggling to get out of VB6's way of sending data, I am doing this to send a byte array from my client to server, please advice if this is the right way,The sending portion:
Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Dim arrNo(3) As Integer
I need to solve the following problem:- Create a server application which generates a random number every second- Have any number of client applications access the current random number through a dll (associated to the server) at anytime How would I do this? Anyone has a prototype VB.Net code for the server which does this kind of thing? I'm pretty sure I know how to write the client code.
My problem is that I would like to know that if some data from client has arrived to the server, I would know its length.Now I m getting an error at: mClient.GetStream.EndRead(ar). It is saying that ar cannot be empty. [code]
As some of you may know, I'm trying to develop a client/server application that requires sending files and text. Text is not a problem, this works fine, and for some of the part, sending files works, but they get slightly mangled in the process. For example, I used a 4x1 BMP that was alternately coloured red and white and tried sending it across. The output was the correct image dimensions, but the colours were wrong. It was more like a very dark red and very dark grey. I inspected the files with notepad, and the header was the same, but the data was different.
I did some research and apparently need to use a BinaryReader and BinaryWriter as opposed to reading the data as a string (like I was when it was being mangled) but now the data is all wrong, even filesize is different.The code below is a simple example of code for reading an image and then writing it again elsewhere using Binary Read/Write.
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.
Ive been working recently on a chat. Ive been using FTP to comunicate through both forms but it need to constantly download the new data and make the application freeze. Even with a Backgroundworker. So my question is : is there a way to keep a constant connection between the form and the host? And not LAN ,I mean that doesnt need to be on the same router.
Im using the code from [URL] as a starter, most of the code is the same. the chat system works fine but on the client a added a disconnect button "clientSocket.Close()" and as soon as i click that i get errors, on the client, this is the code...
Private Sub getMessage() For infiniteCounter = 1 To 2
[CODE]...
And this line...
serverStream.Read(inStream, 0, buffSize) gives me "Unable to read data from the transport connection: A blocking operation was interrupted by a call to WSACancelBlockingCall."
Now im talking the server, after the client clicks disconnect or closes by task manager, looses connection, etc the server crashes and gives me.
I need a walkthrough to : 1. Get a list of available usb ports 2. Send an output signal through the usb (if possible with variable intervals) 3. Close the usb port (so that no signal (current) comes out )
I 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)
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.
