VB.NET socket, Threading and Database Problem - Visual Basic Discussion Boards

tnx a lot! one more pls..can i have sample source code on how to select the data in the database to excel using sql(or another software)?coz the codes that im doing aren't working.in excel,im using macro and pivot table to sum up all the datas automatically.but then,when it generates only the pivoted datas are there.the problem is,to get the equivalent relaycode of the relay monitoring data from database wherein the equivalent data will be put in the sheet where the pivoted datas are.Please..it was badly needed..thanks a lot!!!tc Smile | :)

Hi,
I am a vb.net beginner from another country. So my english speaking is too bad.
My company is doing a project about RSA encryption in VB.net. I know a basic using about RSACryptoServiceProvider class. But i can only to use the random Public key and Private Key by RSA Object in VB.
For example,I already have a pair of keys(private key and public key).That keys are related(The keys were generate by another program).
Now I want to use my public key to encrypt my String and use my private key to decrypt my String. But I don't know how to import my key to RSA Object(Use FromXmlString/ToXmlString).

Please Help Me.(My english is too bad. Please use a simple english)

Hi All

Im trying to connect my pocket pc 2002 to SQL 2000(SQL 8) via wi-fi with vb.net, but appar. pocket pc doesnt support ODBC? Does anyone know how i could do this?

Please help Smile | :)

Paul

You would need to use RDA
Refer
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/sqlce/htm/_lce_rda_intro_remote_data_access.asp

Sanjay Sansanwal
www.sansanwal.com

Hi all,
This is for anyone who has experience with this control or is willing to help Smile | :)

In MSDN, there is a sample of a DataListView class, derived from ListView, that implements a data source for ListView:
http://msdn.microsoft.com/library/en-us/dnadvnet/html/vbnet08262002.asp

Which is great. The problem is this: Let's say I put a DataListView control on my form. Then I perform the following steps to add some columns:

Click on the Columns property and add some columns
Click Ok in the Columns property window when I'm done
(up to here, it's like a normal ListView)
Set the AutoDiscover property to False
Now, I re-open the Columns property window and voila! It's empty! If I look in the code, it DOES create the column objects. When I run the application, I don't see anything, as if no columns are defined. Only if the AutoDiscover property is ON, do I see the columns, data, etc.

Any idea on how to use this bloody control???
Thanks,

/=/=/=/= Sagmam =\=\=\=\

The control code has a check wherein if AutoDiscover property is set to false then DataListView would take default column names from the datasource. To achieve this, existing columns are deleted

Check:

Public Property AutoDiscover() As Boolean
Get
Return mAutoDiscover
End Get
Set(ByVal Value As Boolean)
If mAutoDiscover = False AndAlso Value = True Then
mAutoDiscover = Value
DoAutoDiscover()
Else
mAutoDiscover = Value
If mAutoDiscover = False Then
mColumns.Clear() ' THIS LINE
End If
End If
End Set

Refer:

Auto-Discovery of Metadata
While it is nice that the end programmer can manually specify the columns to be displayed, along with the data fields to which they are bound, we should also provide a more automated alternative. Ideally, the control should be able to examine the data source and use its metadata to determine all the available data fields. Column headers can then be created for each field so the control can bind to all available fields.

Sanjay Sansanwal
www.sansanwal.com

Thanks, I've noticed that too, only I wasn't sure why it happens in design time. I also noticed that, unlike ListView, the Designer doesn't add the "MyList.AddRange(...)" statement to the InitializeComponent method. Even if I add it myself, it doesn't help because there's another problem: you cannot have unbound columns within the list (mField = nothing).

So all in all, I wish I had a better way of doing this other than manually build my list view, but I don't. I'm just not so good with Designer-enabled user controls, so I don't know what to change in DataListView in order to make it better for my needs. The best I can do is create a DataListView of my own that is not Designer-enabled.

/=/=/=/= Sagmam =\=\=\=\

OS: Winxp and Win2003
Visual Basic.NET 2003
MS-SQL Server 2000

hey all

I am a newbie in vb.net but i have managed to build a simple chat server in vb.net using socket and a client connecting to it made in vb6. Some of the code in the server are based on the basic samples that i get from other authors. To give you an idea, the server uses sockets, multi-threading and a database connection to MS-SQL server 2000. the off line messages, contacts lists, current status of the rooms and conference rooms are stored in the database. The client app is already done and it already meets the requirements for connecting into the server, but my server has not been optimized to do its job since i am in the code,debug and learn level, i'm still trying to make it stable. But during my testing of the server it pops an error which i haven't solved for a few weeks now especially if the server is running for a longer period of time. I have searched to a number of sites but i wouldn't give me the exact solution to my problem.

Problem:

1.)Once the server is running more than 24 hours and receives a bunch of chat messages from the client application it tends to slows down its response to the client although im testing it on a single user connection, what i did was only send a test flood of messages , then connect and disconnect a hundred times.

2.)After a hundred of test flood messages to the server and connect/disconnect session from the client, the server pops an exception error such as “operation not allowed on a non-connected sockets” but when i click ok button of the msgbox my client app sees that it is still connected to the server. The client could still send commands such as [user search but not on private and room chatting anymore] .

3.)When the server tries to save a data into the sql server it then gives me another error “the statement has been terminated”.

4.)the problem that i mostly see is during login, private and room chat, saving to database. Other strange behavior of the server is that it can still recieve a search user command and then reply for the result but when i try to do private or room chat, there it pops the error messages again and no reply to the client whatsoever.

Questions
1.)Do you think vb.net can handle more than a hundred concurrent user online or more or maybe thousand?
2.)Do you think its a good choice to have the client built in vb6 and the chat server built in vb.net ? any ideas are welcome

Frown | :(

Guys please i really need your help with my problems ! especially on socket and multi-threading. Any comments, suggestion or modification of the code are welcome. I have provided the server code in my site, I've omitted some of the codes and classes, to get you into the direct point, i have posted additional information of my problem in my site and some other screen shot of the error.

my site:http://www.geocities.com/jimmypearly/index.html
Thanks
Jim

PS sorry for my poor english.

-just make it tough

jimmypearly wrote:
1.)Do you think vb.net can handle more than a hundred concurrent user online or more or maybe thousand?

Yes. It's not the language or the .NET Framework that will be limiting you. It will be the server software licensing (Windows Server that is...) and the design of your chat server.

jimmypearly wrote:
2.)Do you think its a good choice to have the client built in vb6 and the chat server built in vb.net ? any ideas are welcome

You COULD use VB6 but I wouldn't recommend it since it's essentially deprecated. Writing the clinet in VB.NET will give you the most flexibility.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

I'm creating a few programs for chat/email purposes. The idea was for there to be no central application and each program connect to the others kinda like in a p2p network (i think). I've not really got any idea how they are going to know what ip to connect to if each time the user connects to the net they get a new ip. I'm using networkstream and tcplistener/client because thats all I know how to use. Any ideas or even pointers towards classes better suited to this would be great.

Thanks

That's the whole problem of any P2P network: finding peers. There's not a single solution and not a perfect solution. You can try connecting the last peers seen, have a central server for locating peers, or some always-on, highly-reliable peers.

Yes, even I am blogging now!

i will be grateful if someone can give final year project ideas

Create a Pocket PC application for taking orders in a restaurant

Sanjay Sansanwal
www.sansanwal.com

Hi Everyone!

I need a help. I am in proces of development of Instant Messenger and Conferencing Tool. What I need is a support for proxy Server Also.

Like if you are behing Wingate Proxy and you want to Use the option for proxy Setting.

Like in MSN --> Tools --> options --> Connection --->

I want all the feature of this page.

Let me know if any one can help me. I will be really grateful.

Thank and Regards

Irfan Haider Jaffery
Software Engineer

Here is some code that has proxy settings implemented.

http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=1961&lngWId=10

I am wanting to create some small apps for Pocket PC. I have VB .NET 2003 Standard. I have installed eMbedded C++, eMbedded C++ SP4, and the CF 1.1 SDK. I still see no option under new project to create a VB porject for Pocket PC 2003. I DO NOT want to do a C++, J++, or ASP project but VB .NET CF app. Can anyone help me? What have I not instaled/configured? Does this only work with the PRO version of VB? I have searched and searched but the hits are overwhelming and generally unrelated to setting up to create apps in VB for Pocket PC.

Thanks for any help,

Glisson

Glisson wrote:
I still see no option under new project to create a VB porject for Pocket PC 2003

It is called a "Smart Device Application".

Glisson wrote:
Does this only work with the PRO version of VB?

Not sure about that.

"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell

Not getting the response you want from a question asked in an online forum: How to Ask Questions the Smart Way!

Yeah I remeber seeing that on some boards now but I do not have that option. It's driving me crazy too! I really want to play with that feature!

Glisson

It's NOT supported on the Standard or Academic Editions. You must have the Professional Edition or better.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Thanks for clearing that up. Even thought it's not the awnser I was looking for! Man that is a bummer! Looks like I need to start watching E-Bay. I can't justify paying retail for no more then I have planned or am likely to accomplish. LOL

*EDIT* I forgot about the Acedemic versions. I started digging up some more info and according to this site msdn feature comparison, it IS supported by the Acedemic version. Guess it's back to school for me. LOL

http://msdn.microsoft.com/vstudio/productinfo/overview/academic/features/comparison.aspx[^]

Thanks again,

Glisson

Hi,

I am building a simple windows form which mimics the windows media player.
It user the wmplayer control, and has as transparencykey white.

For some reason the player does not play the video files correctly. I hear
the audio part but the video part is not displayed, except some flickering
iat the start. If i dont have any colors as transparencykey it works fine.

How do I fix this issue?

thanks

are you using a bitmap or picture loaded as a resource?

If you are then load it as a file instead I have seen this be an issue before.

I just specified the a png file as the background image of the form. How would I load it as a file?

thanks

Me.BackgroundImage.FromFile("c:\windows\clouds.png") ' whatever your path and file is.

The problem exists even if I dont specify a background image. Frown | :(