Difference Between Sync And Async Connections In A Tcp/ip Client/server Application?
Sep 2, 2009a small question: what is the difference between sync and async connections in a tcp/ip client/server application?
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VS 2008 Async Socket Connections - Clear Out No Longer Useful Sockets From The Server?
Dec 18, 2009I have been developing an async socket connection server and client program. I have been testing it, and noticed that if I connect to the server from my client and then disconnect. Upon reconnecting I am on a different port(local IP still). This is fine, however when I go to send a message, and the server trys to update all the clients, it eventually hits clients that do not exist anymore. I get the SocketException 10054, and upon connecting/disconnecting enough, it no longer works at all. My question is how do I clear out these no longer useful sockets from the server? I am doing currentsocket.Shutdown(SocketShutDown.Both); and then a currentsocket.Close(); after that. When a user disconnects.
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Async Sockets Client-server?
Jul 25, 2011I'm using vb .net 2008 with 3.5 framework. (the following 2 classes are put in a DLL that i import in a main application)
Server class:
Code:
Imports System.Xml
Imports System.Net.Sockets
Imports System.Text
Imports System.Net
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Basically in my main application i am instantiating the client class from this dll, as well as the server one. On the client form i got a "send data" (SendFISA sub) and a "connect" button. After connecting the client and clicking on the "send data" i am sending to the server a string formed of some information created when instantiating the client class from the dll (i can't make that type of data public, but i'm just using a constructor to assign values to a class object, nothing special).
Now, when the server receives the data sent by "send data" button click it responds with "PKG_SENT" corresponding to the "FISASENT" string terminator(in the module) of the string that was sent. The "WRONG_MSG" constant is for when the string terminator is different from the 2 from above.
On the local disk, if the server cannot be reached, the client saves an xml file with this data. In the dll i made a timer that ticks every 5 seconds and checks to see if there is any xml file on the disk and sends it to the server if the connection is ok (trimiteXML sub). The server would respond with "XML_SENT" corresponding to the string terminator "XMLSENT"(in the module) appended to the read string from the xml file. After the file is sent it is deleted from the local dir.
The problem occurs when i click "send data" AND there are XML files to be sent from the disk. I believe they are interpreted by the server somehow at the same time because the message is neither "PKG_SENT" nor "XML_SENT", but it becomes a combination of the "WRONG_MSG_TYPE" and "XML_SENT", "XML_SENTG_TYPE". I have no idea why this is happening and i basically want the socket to wait with sending the files from the disks until the "send data" finishes.
Difference Between SQL Server Native Client And SQL Server DSN To Support SP Execution?
Jul 9, 2009I wrote a VB code to call a sp in sql server 2005, which returns a recordset as follows:Dim objRecordset As ADODB.Recordset Set objComm = New ADODB.Command
Set objRecordset = objComm.Execute If Not objRecordset.BOF And Not objRecordset.EOF Then
Set objRecordset = objRecordset.NextRecordset I need to continue to get next recordset since there are many select statements inside the sp which I need to get the data. The code works fine when I create the DSN using SQL Server but it does not work when using the connection string or SQL Server Native Client DSN. It either breaks at Set objRecordset = objComm.Execute ( connection string )or at If Not objRecordset.BOF And Not objRecordset.EOF Then(SQL native client )
I have worked on this for a couple of days now and could not figure it out.Is this a bug in SQL Native Client or something related to some configuration on the database side? IS there a way I can change the connection property to get this working using SQL native client or connection string?
Windows Application And Web Server Connections?
Aug 17, 2010I have a .net window application created and I wanted to see if it's at all possible to place various file dependencies off the web server. e.g. is it possible to have the connection to the database be off a web server?
I also would like to see if it's possible to place one of the .dlls off the web and have code that points to it to load.
.Net SQLClient Connections And SQL Server - Active Connections Reflect Even Though All Closed?
Jul 19, 2011Using VB.Net and SQL Server 2008 R2: I have recently had a database that using sp_who2 reflects a connection ".Net SqlClient Data Provider" is still active even though the .Net application has closed and disposed of all connections.
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Server/Client - Basic Tcp Server/client Application
Mar 30, 2009I'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.
Asp.net - Database Connections Work Fine When Application Is Run From Localhost. Login Fails From Dev Server
Jun 11, 2009I have an application which connects to a database, retrieves a username from a user's table and matches it against the username retrieved with System.Security.Principal.WindowsIdentity.GetCurrent.Name.On my localhost, everything works fine. The database exists on the development server but the application lies on my localhost. All of my authorization and authentication techniques are running smoothly.However, when I publish my application to the development server, I'm faced with the following error.Cannot open database requested in login 'databaseName'. Login fails.Login failed for user 'DevelopmentServerNameASPNET'.
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SQL Server 2008 Configuration For Client Server (Windows Form) Application
Apr 6, 2012Case : I'm creating an application (desktop application) with VB.NET (actually windows form), and using SQL Server Express 2008 for its database.
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Client Server Application - How To Make Clients On Sql Server
Sep 24, 2010How to make clients on sql server i mean when i will install my application on clients how i will connect it with sql server?
View 6 RepliesRemote Desktop Application? Safe To Use Winsock In Creating A Client/server Application?
Jul 18, 2012Im planning to create a Remote Desktop Application and I'm having problem with viewing other computers monitor or screen.
Im not asking for the code on how to do it. and one more thing is it safe to use winsock in creating a client/server application?
Build Client-server And Sql Server Application?
Oct 26, 2009i'm newbie in this programming..i need some references or a starting guide to build an sql server and vb.net application.
View 3 RepliesClient Needs To Have Sql Server On His Machine If Application Uses Sql Server?
Jul 16, 2009I am creating small application (desktop search engine) which uses sql server as back end. Sql server is used to store huge data using indexing (for quick search). Is it necessary that client should have sql server on his machine to run the application? I don't want to install sql server on client's machine, because my application is just a small utility.Is there any other way so that I can store huge data using indexing?
View 2 Replies.net - Port Sqlite Application To A Server/client Application?
Jun 4, 2012I have wrote an Application for a organisation and they had let the app run in their lan using Samba, it worked perfect. Now they want to work over the internet.The Problem is that I have written this app with Sqlite, that means its currently working so:They have a exe and the sqlite dll and the sqlite database on their samba server and they connected a network drive on their windows pc to run it. So that means every pc is writing over samba to the sqlite database.
I tried it over the internet, but like i thought sqlite is a local database and its very slow, even if the ping is under 50ms. I could create a tcp server, that handles all and writes all to the sqlite database, but I have already written around 20.000 code lines for the project, so that would be not the best option for the lazy me. I have used only one sqlite class in my client for querieng, so I thought that it could work without much work, if i would replace the sqlite database adapter with the mysql database adapter, since sqlite has nearly the same syntax then mysql.
VS 2008 TCP Server / Client - Client To Send The Server 4 Numbers - Depending On The User's Choice
May 9, 2009how 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 RepliesVS 2010 : Send Data From Client To Server (encrypted) And The String Sent From The Client Is Not The Same As Received From The Server?
Jun 27, 2011Hey 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)
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VS 2008 App For Sync Files On Client With Central Computer (VPN)
Jun 22, 2009This is the situation: i have the central location with the main computer,and 14 distanced locations connected in VPN and often we need to update program manually (on distanced locations) by overwriting the existing .dll-s of the program and this is pain in the ass to connect remotely to 14 locations and on each workstation overwrite the .dll files so i want to create application which is going to be installed on each WS and by running this app it will check the program folder on central computer and if there is any file with newer version then existing one on the WS it will copy it from central computer and overwrite the old file/s on WS. It is a small app with two buttons and progress bar but the main thing is the Update now button because i dont�t know which commands it should commit.
View 22 RepliesClient Server Application In .net?
Jun 4, 2011i 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.
View 1 RepliesApplication Is Now Running On Server Or Client?
Nov 8, 2010I use VB.NET for a Windows application.
How can I find out if the application is now running on a server or client (programmatically)?
Build A Client Server Application?
Jun 3, 2011i currently have a project. The application created in this project will be located in a server, and some machines can access this application at the same time. The problem is, i don't know what's needed to connect that application to several machines. I know how to build this application and run it in a single machine, but i have no idea about running this on server.
View 3 RepliesClient Server Windows Application
Oct 28, 2009I have developed 2-3 standalone windows application using VS2008(vb.net) + Sql server (2008,2005) and quite comfortable with stand alone windows application. Now i am trying to make a windows app which will share a server database on LAN. I googled alot about this but still no success. So i decided to make that as stand alone app and i just changes the connection string to use remote server database. Everything is working fine still. All the insert, update and delete query are same as stand alone n me not getting any problem while testing through one more remote client system. But while googling i heard abt "CONCURRENCY" control.So please guide me is anything wll b wrong in future wid my this application when i will deploy this to my users? What about locks and how can i implement this to my Insert, update and delete queries to control concurrency and maintain integrity ?Please guide me step by step becoz i m new be to client/server application.
View 7 RepliesClient-server Chat Application
Jan 15, 2012I made one client-server chat application using vb.net. I want to know how can i change the form/icon color when a client sends a message and vice versa.
for eg: like in yahoo messenger or msn messenger,etc, How i user knows when he receives an message.
Create A Server And Client Application?
Jun 7, 2009I am trying to create a a server and client application. All that I want to do is have a client that has a picture box. The server will send an image to the picture box and the client will display it. I have looked online to find some tutorials but most of them just show how to do a connection and usually only with a console application.
View 3 RepliesCreate An UDP Server/Client Application?
Jul 8, 2011Create an UDP Server/Client Application?
View 3 RepliesCreating A Server Client Application
Jan 21, 2011First of all, I want to say sorry if this is not a correct forum. I have built several standalone applications up until now. But now I need to create a server client application, the only database is on the server. The application itself is installed on all the client computers but not all of them are granted the same level of access to the database.
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MultiThread In Client Server Application?
Aug 9, 2009SERVER
Im using this code:
Imports System.Threading
Imports System.Net.Sockets
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but when i tried to run the application, it hangs even if i wait several minutes.., is there something wrong with the code..
Server Client Interface Application?
Apr 13, 2011I want to create a server client application in which The server will communicate with the client and give them commands. I did the same in visual basic 6.0 using Winsock component.Now I want it to implement using Visual Basic 2008, how to do it and which component to use.
View 5 RepliesMySQL Connections From Client Programs Persists
May 15, 2009In a college where I'm employed, we are currently testing (dry-run) the new enrollment system I have developed. The application has several modules (accounting, cashiering, course scheduling, admission, advising, grading) installed in different offices. We are using MySQL Server 5.1 and the front end was developed using VB.Net.
The system has 1 computer server and 25 clients. I have noticed, using MySQL Administrator, that the clients' connections persists although I have used using syntax for all my data access/manipulation codes. I thought after end using statement the connections would automatically be released.
Access Or Run File From Server In The Client Application?
Sep 15, 2011I would like to ask some advise for the best thing to do regarding with this matter. Im working with a client-server application and I should run a pdf file from the server in the client application. The file name is the only saved in the database(MySql) and the full path is in the server. What technique should i used i order to access this file in the server., I planned to use the winsock. Im working in vb.net.
View 1 RepliesClient Server Application That Uses File Sharing
Mar 3, 2009I want to build an application(the client and server) that the clients would be able to see and modify only certain files on the server depending on their credentials. For example, a specific client can read/modify a word file, but another cannot. And the server should specify which client has which rights. After a client has made any change in a file, every other clients should be notified by email. I've read some articles about .Net Remoting but I still don't know how to make a client see/modify files on the server.
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