Client-Server-Client Multithreading - Instant Message Another Client
Jun 21, 2010
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.
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])
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 have been reading through Atheists posts in regards to client-server and TCP client/server connection's. But how do i go about writing a program with 1 client and server where the client side creates a text file.Once the server sees there is a text file it connects and downloads it to itself or the client pushes the text file to the server.Once on the server i will read the text file and put its info into a sql db.
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.
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")
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've basically made a basic tcp server/client application. The thing is that I'm behind a router and so will be the other people that use my clients. I've had to use port-forwarding or the software "rinetd"to run quite a few applications online.
Let me explain: I'm on a lan network that connects to the internet. Whenever I want to host a server - for instance a basic ftp or http server. If I give my external IP to anyone, they won't be able to access my server. Even if I portforward, it doesnt work. I have to use rinetd here. For other applications, portforwarding works. I'm not sure how these things work at all.
Anyway, my issue now is that I have created this server/client application. I'm having serious doubts that if I run the server, I'll have to either a) portforward or use rinetd to get people to connect to my server. IF I need to portforward, that's fine. However, using rinetd would really suck... My 2nd concern is as follows: IF the person running the client is in a similar situation as me (i.e he's on a lan that has a router which connects to the net), will he have to portforward or use rinetd as well? If he portforwards that's fine. But I don't think I could get people to use rinetd.... Also, if there are more than 1 person on a lan trying to connect to my server, there is a big problem when they try to portforward: they will only be able to allocate one of their internal ip to that port, and the others won't be able to connect, right? How does this work? I mean, I use many softwares like msn/skype/(some games)/firefox that do not need portforwarding/rinetd. Yet they work. My housemates(other people on the lan) use the same softwares, and it works fine. There's no clash/probs watsoever How come these run fine?
Anyway, back to my issues. Given I have no knowledge about how the above work, I was wondering whether there was a way to host a vb .net server application on an external website (external to my house) so that I might *avoid* the above mentioned problems, and to what extent that would be a sound solution.
I have got the server app an the Client app Both Working to what i can see But My issue is i was only asked 4 days ago if i could add a Private msg and Whisper Feature as well as admin controls I have Done what i could to it then realised i have no idea how to only send the data to the selected client.
i have been working on a chat program Server side and client side i have most of the features i was asked to put in but then once i got most of the bugs out i noticed something the server admin could send whispers and alerts to single users but then when you try do do it on the client side it wont work so i looked through it all and found my issue the user list on the client is only a list of the names in server hash table so i was wondering how do i send the hashtable and all of its data E.G. user connection information to the client so that it can send commands to individual users like the server side can
vb Public clients As New Hashtable() ' This subroutine checks to see if username already exists in the clients ' Hashtable. If it does, send a REFUSE message, otherwise confirm with a JOIN.
[code]....
i tried to send the hashtable over the same method used to send the user names to the client but it cannot convert the hashtable to a string so that wont work so my question is How do i send the hash table to the user from the server then display the username on the client ??
i made a tcp/ip application using the .NET TcpListener class, my problem is that sometimes (about 30 / 4000) the connection between the client and the server got interrupted in the middle and the server response to the client is lost.is there a way to know if the server response was successfully sent to the client without the client response back?
I have an application that takes a series of reports and sends them as attachments in an email to a specified group of email accounts.
When I run the Java version of this using apache commons and the same setting, the email is sent. However, when I run the VB.NET version of the code, it fails on my local machine and on the client machine.
I have a VB.NET web application running on a server that uses similar code. I tried that code locally and it fails. Yet, the web application is working perfectly.
Why is it that the Java application can send the email, but the .NET application cannot?[code]....
this is probably easier than I think it is.I would like a client-to-client messenging system without using Winsock if possible. At the moment an IP based connection system would be okay.
Can't find any free ones so thought I would work on one on my own for the heck of the learning experience with TCP stuff.I'm about ready to start on the messaging aspect of it.The biggest thing I'm wondering about is figuring out when people are online.I'm not too sure how the whole thing works.Say I turn on my messenger. Would my messenger just send a message to all IPs on a certain port to say I'm online and then wait for a message back from the IPs that can return messages and then figure out who is online that way?
Client/Server Application in vb.net 2010 i have created but it was just basic one. I need to show send data from client to sever and sever to client and and more functionality. (like showing price ot item or anything
I am struckup with a problem from last two days. I am creating a web application using VB.NET, Ajax & RAD Controls. When user clicks on a button I want to open a RAD Window and show the list of ledgers available to the user, so that he can select one from the list. And to open that window I have to call a java script function from client side, which is already achieved using the below code.
I need to return an error message to the client, if they have entered invalid data when calling my web service. So if my code is: [code]Is there a way to display a more user friendly error message (such as a message box or just the words "Invalid Order ID")?
Is that possible to done this? If yes, how to done it?
Client: [Client is made in VB.NET] Add new form: "Login Form" Add new form: "Form2"
[Code]...
if it is "LOGIN" then check is the username and password correct, after that send back to the client that the information is true so the client will show up Form2
if it is "REGISTER" then add new username and password to the server *NOTE: The username and password will be saved in a file
i am creating a client server application using vb.net with odbc as my data source to sql server 2005.send me a code that will enable the application running on a client machine to connect to a remote server.the application is to run on LAN and other client machines are on same domain.
My first post here in vb forums. I'm new to sockets programming since I migrated from Winsock and I learn a lot from Atheist. using his code, I can't access the messageReceived() every time a client sends a message on the server. but then I put a code to catch the message on sub doRead() and I can retrieve the message. My problem now is how can I determine if a client is still connected to the server or not so I can delete it on the ConnectedClient ?
[Code]...
Note: the server runs on Win7 x64 ultimate and the clients are laptops on win7 x86. I read a comment that the server should be having a static IP address, but when did it together with the clients, It still doesn't work. I am just using a switch for the network.
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.
i have created 2 app one as server and one as clinet i need to be able controling the clinet from server ex: 2 media player clinet/server i must be able to stop,play,mute song from server i will put the code server :
