I have herd that a new type (or old type) of connection when the server connects to the client. Is it really possible to do such a thing with mulit-Servers trying to connect to one client.How would I make one like that O.o.
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I found similar forum thread [URL], but he don't have answers. How I can conncect | send | recive data using tcp connection with specific internet service (not web).
View 1 RepliesIs there a way to time out the connection? And loop to retry until it can connect?
View 1 RepliesWhat are the basics to creating a tcpclient / server?
View 3 RepliesI have a simple tcpclient/server messenger running. Everything works great, except for when a client exits the software. When someone exits, is crashes the server with various exceptions and the server has to be restarted, as well as the clients. What I am looking for is a way to properly "log out" a client BUT leave any other connected client on so that is no break in the chat. Then the person that logged out or a new person can join back in whenever they choose.
CLIENT
''CHAT SERVICE
Dim clientSocket As New System.Net.Sockets.TcpClient()
Dim serverStream As NetworkStream
Dim readData As String
Dim infiniteCounter As Integer
[Code] .....
However I have hit a massive brick wall with my program. My program that I'm trying (can't emphasis this word the importance of that word) to create a Client/Server chatroom using TCPClient in Visual Basic. So far I can get my client to speak to my server. However, i'm trying to get the returned data to display in a listbox which never happened, i then tried a label, which again never happened then a text box which I'm sure you can figure out how that went! I'm not great at networking programmers nor am I not bad I'm terrible but duty calls when it comes to projects.
The code I currently have was mostly taken from the net but when I have the program fully work and I understand how the software works I intend to heavily modify for it to suit the needs of what I need to achieve. where I can get my client to display the data from the server that I have already sent to the server (which displays successfully within the server).
[Code].....
I have multiple TcpClient connections to my program. The connections exist as instances of a UserConnection class, that fires events on logon attempt and when receiving messages. My program also holds a Users object, which is a list of a User class objects, holding saved data (username, password etc) for each user that is allowed to log in.
It seems convenient to put a reference object of the respective user, in the UserConnection class (when successful login is verified). Hence, when an event is raised by the connection, the connection object will hold the user reference. As any event handler logic will need to know which user is responsible for the event.
If I don't make a user reference in the UserConnection class, then I need to loop through the users (less than 20) each time, to find the correct user. Not a big deal maybe, but i'm looking to understand how it would be done by an experienced programmer.
When data needs to be sent to a user, I need to access a UserConnection object. Hence the User class also holds a reference to the UserConnection class.
i know how to make a tcp ip connection using tcpclient and so on. But what i want to know, how to transfer file in a specific computer?
View 2 RepliesI am writing a VB.NET app that connects to a legacy application using TCP.
The communication is working fine and is very quick once connected, but there is always a delay (of around 2.5-3.5 seconds) when I create the new connection even though I am connecting to my local machine[code]...
I am creating an authentication server for some projects I'm working on. This authentication server works by receiving and transmitting data to users trying to authenticate. The user can send data to the server succesfully but when sending back it requires port forwarding. I read a way that I would not require port forwarding by using reverse connection but I have no idea how to get it working. I found a tutorial and tried to implement but when it tries to connect to read the stream it says the connection is refused.
View 1 RepliesI have simple code that connects to Sql database... (well it doesn't)
VB
Dim objConn As New SqlConnection("Server=localhost;uid=***;pwd=***;database=***")
objConn.Open()
ERROR MESSAGE:A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)But looks like something is wrong with "localhost" thing. Any help? Where can I get name of (my) server?
How would i send different types (.png/.bmg/.mp3) of file over a tcpconnection (server / client)
View 2 RepliesI have a .Net program that has to run on a cluster of server 2008. To find out the right IP I resolve the dns by GetHostEntry(VarDefinedInfConfig).AddressList(0)
but when I am converting my old code (this code picks the wrong IP) dns.GetHostName().AddressList(0) => this returns a virtual IP and not the right one.So I changed my TcpListener to (dns is parameter from config)Dim listener As TcpListener = New TcpListener(New IPEndPoint(Net.Dns.GetHostEntry(dns).AddressList(0), 8001))
listener.Start()
[Code]...
Am using this code to connect to an SMS server to send sms to mobile phones but am getting stucked at the the bold like below:
[CODE]:.....................
I need to create an unordered list of dates for a news items archive... It should look like this
2011
Dec
Nov
[Code].....
I can carry on with this adding in the for loops for months nested under each year however it doesn't seem very practical and will generate links for months even if there are no news item entries...
Is there a way I can build this tree automatically and only include the years/months that have news entries. I can pull a list of SQL Server timestamps from the DB for all the news items and then would like to populate the list based on that...
I am trying to connection to MS SQL SERVER 2008 database (students), i want to make sure:
1) If connection string that i made is OK
Dim connectionString As New SqlConnection("server=X86ONX64; database=students; Integrated Security=True")
2) How can i check if dataset is producing any results?
Code:
Public Class Form1
'Connection String + DataAdaptor + DataSet
'Declared Outside Any Subroutines/Functions
[Code].....
My application is VB.net 2008 with sql server 2008 , the application is working on the server . whereas in the client i got the error which i attached below Error" A Network - Related or instance - specific error occurred while establishing a connection to sql server. The server was not found or was not accessible.Verify that instance name is correct and that sql server is configured to allow remote connection"
View 1 RepliesI am trying to find out if the connection of my sockets (TCPClient) is connected or not connected. I am using the following code:
[Code]...
I have a problem with a connecton from VB.Net to SQL Sever 2008. My code like this:
[Code]...
I'm trying to make a connection to SQL Server 2008 express Using this code
Dim Ordr As String = "Select * from Orders"
Dim con As SqlConnection = New SqlConnection("Data Source=localhost;Integrated Security=SSPI;" & _
"Initial Catalog=Orders")
Dim com As New SqlCommand(Orders, con)
[code]....
I get this error:A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server
I created a vb form application that I want to query a SQL Server database that is hosted through godaddy. Below I have my function that calls the db and also my connection string in my app.config file. When it tries to open the connection I get the following: {"A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)"}. Do I have to set something on the godaddy end to allow a connection? Or can I only access the database from a web page on my site? [Code]
View 2 RepliesI'm having problems tring to connect to the sql server 2005 express with and vb 2008 express.
I keep getting this error and here is the code too:
Login failed for user 'CHRIS-ARTZGuest'
connFabList = New SqlConnection("Data Source=CHRIS-ARTZ;Database=FabList.mdf;Integrated Security=True;")
I need to reverse a string of words without using the reverse function. This is what I have so far, BUT it only shows the last two letters. For example: if i type "John" it will only give me "ho"
Public Class frmReverse
Dim original As String
Dim New1 As String
[code]....
I need to this without using things we haven't seen in class.
After running the following sub (VS debugger), I try to detach the database in SSMS, but it shows the connection open still and won't let me detach. If I close program in debugger, the database shows no connections. I check the dataadapter's connection in the finally block and is shows closed. What gives
Private Function ClientMasterDBFiles(ByVal MasterClientDBConnection As String, ByVal DBName As String) As DataTable
[Code]...
Error message receiving A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) The project is written in VB.Net 2008. Production server uses SQL 2008, Dev Server uses SQL 2000. The application has been built and published.
Prod Connection String: strCN = "server=SGMAGNCPQ03.;Initial Catalog=APO_Tax;Integrated Security=True"
Dev Connection String: strCN = "server=S04423711940995.;Initial Catalog=APO_Tax;Integrated Security=True"
The Problem: When I change the connect string from dev back to prod and try to run my app, I get the above error message. If I reboot everything works fine but if I switch the connect string from prod to dev and try to go back to prod, I'm back to the same problem.
This will happen at random, and I can always just catch the error and re-establish connection to the server, but I am confused as to why. When doing lots of inserting into the sql server, I only establish one connection that is public, instead of many little connections. I had my doubts on a public sql connection, but it's been running great, and I've seen no problems until this morning. Again, this random moment I hit an error that stated, sql connection state is broken. Is it bad practice to just accept this error, and when it happens, re-establish the connection?
View 7 RepliesI've been working on a program where clients will send short messages to a server.[URL]
On the server side, this code is running to check for incomming messages:
Private mClient As System.Net.Sockets.TcpClient
...
Do
bytesRead = mClient.GetStream.Read(readBuffer, 0, BYTES_TO_READ)
[Code].....
is there a way to send a command to start a prog on the tcpclient side.
View 3 RepliesThis emailing code wont seem to work in my program. I get an exception "The SMTP server requires a secure connection or the client was not authenticated. The server response was 5.5.1 authentication required."
Imports System.Net.Mail
Public Class emailStudent
Private Sub sendEmailButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles sendEmailButton.Click
SendMail()
[code]....
I need to know when a TcpClient disconnects so I can properly free up the socket and process anything in my program that needs to happen when a client disconnects.
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