Visual Basic

Ujjaval Modi20-Dec-07 1:39

Ujjaval Modi

20-Dec-07 1:39

Hi,

I think if you will set the Font property of that particular textbox to Arabic font, then whatever text is entered in the textbox will be in Arabic only and you wont need to validate it.

Regards,

Ujjaval Modi Smile | :)

Manpower moves wrenches, horsepower moves cars, and the power of the mind moves the world.

hassanasp20-Dec-07 13:06

hassanasp

20-Dec-07 13:06

please send to me code

Ahmed hassan

Christian Graus20-Dec-07 14:23

Christian Graus

20-Dec-07 14:23

Please don't ask twice. Also, there is no code. DId you understand the answer ? I was wondering myself, if a computer is set up to be arabic, what other characters would you expect ? Or do you just mean to reject numbers and symbols ?

Christian Graus - Microsoft MVP - C++

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

Connecting two computers using VB.NET

Paul Conrad22-Dec-07 13:07

Paul Conrad

22-Dec-07 13:07

You already asked before. Don't keep asking the same thing over and over. It is rude.

"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon

Benny_Lava19-Dec-07 23:58

Benny_Lava

19-Dec-07 23:58

Hi,

As the title says. I need to directly connect two computers or devices that have my software using IP addreses. And to share files between the two computers.

Example.

I select from a list IP address that I previously obtained, I connect to that IP adress and upload or download some files from it.

How to handle such a transfer?

Any ideas?

Thank you!

Re: Connecting two computers using VB.NET

Dave Kreskowiak20-Dec-07 7:42

Dave Kreskowiak

20-Dec-07 7:42

One machine must be running some kind of server to handle it's end of the file transfer and the other must be running a client that talks to that server.

There are a ton of different ways to do this, but to get any kind of an answer you're going to have to be more specific about what you're doing. Are you transferring files as part of a peer-to-peer chat application? Is this a central server that's going to hold these files? Can you use a normal FTP server as part of your app? Do you know anything about writing app's that use sockets?

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

How to Control Concurency using Threads in vb.net

Vimalsoft(Pty) Ltd19-Dec-07 23:17

Vimalsoft(Pty) Ltd

19-Dec-07 23:17

Good afternoon All

i have an Application in an Multiuser evironment, i have a Concurency Problem. i would like someone to Explain to me how to handle Concurency using thread, i would like to lock the Update Function when one of users is updating the records and unlock it when the process is done . here is an example of my code

Public Function SaveProperties_Lis(ByVal dsDAta As PropDAL.Dssearchlis) As PropDAL.Dssearchlis

Dim ws As PropDAL.Properties 
Try

ws = New PropDAL.Properties 
'check the Business Rules 

Me.CheckRules_Lis(dsDAta) 
'Updating the dataset 

dsDAta.EndInit()

ws.UpdateLis_search(dsDAta)

Catch ex As Exception 
MsgBox(ex.Message)

End Try

Return dsDAta 
End Function

.

i have this Function in BLL(Business Logic Layer). i want to lock it , when another user is using it.
The Bll is running on the Client machine and its a DLL that is deployed with the Application. i need to trap the Concurency situation in the BLL. The code above is retreaving the data from the DAL(data Access Layer), so the BLL will create an object of a DAL and use the DAL functions, and the Client application will call the BLL for service by creating an object of BLL and use the methods of BLL that will use the methods of DAL, i have not prevented Concurency to a database,and thats what i want to do. i want to know how to achieve this in a multi user Environment.

Thanks

Vuyiswa Maseko,

Sorrow is Better than Laughter, it may Sadden your Face, but It sharpens your Understanding

VB.NET/SQL7/2000/2005
http://vuyiswamb.007ihost.com
http://Ecadre.007ihost.com
vuyiswam@tshwane.gov.za

Re: How to Control Concurency using Threads in vb.net

Dave Kreskowiak20-Dec-07 7:56

Dave Kreskowiak

20-Dec-07 7:56

Theading has nothing to do with concurrency issues in the database. This question is not answerable, as you've posted it.

Concurrency is a situation that your app must handle according to your business and data rules. Noone can tell you how to write an "all encompassing solution" to a problem you haven't explained yet.

Locking a table is NOT a good option since noone will be able to read that table until it's unlocked. This too will genereate it's own set of problems for your app. If you wanted to kill your SQL server's performance from your applications point of view, this is the way to do it.

From your description, it looks like you don't have a firm grasp of what data concurrency is, what situations cause concurrency violations, nor do you understand what your options are in handling various concurrency issues and what the implications are for each solution. I highly suggest reading up on data concurrency before you start throwing locks around that you really don't need.

Think about this situation. Say one copy of your app places a lock on the table, then crashes. When does the lock get removed??

You can read up more on Data Access and Concurrency issues in this[^], this[^], and these[^].

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

Bitmap&Bitmap

The real $M@19-Dec-07 22:22

19-Dec-07 22:22

Hi!
I've the following problem:
I've two bitmap variables, and I want to check that they contain the same image or not.
If I try to use the "=" operator, I get an error message.
I wrote a function what examines every pixel (by setpixel and getpixel methods), but it makes the program very slow.
Isn't there a faster way?

Thanks in advance.

Christian Graus19-Dec-07 23:26

Christian Graus

19-Dec-07 23:26

Because VB sucks, no. But, if you did this in C# and called it from a dll, you could use direct pixel access, like I do in my image processing articles, which would be faster.

The real $M@20-Dec-07 23:36

20-Dec-07 23:36

Thanks

MikeMarq20-Dec-07 11:24

MikeMarq

20-Dec-07 11:24

Yes I had the same problem with get/setpixel. Here is what you do, create a file stream for each file then compare the file streams.

If you need an example just let me know (don't worry it's real simple). I don't have the exact commands for it memorized but I have code for something similar on my laptop and I can give it to you later if you want me to.

The real $M@20-Dec-07 23:35

20-Dec-07 23:35

I'll be very grateful if you send me the code.
Much thanks

MikeMarq21-Dec-07 8:44

MikeMarq

21-Dec-07 8:44

A few notes. This will compare 2 files of ANY format not just bitmaps. path1 and path2 are your file paths. This will only work if the files are the same format(if you compare a 32 bit and 24 bit bitmap it will always return false). Also I have not tested this but I think it is correct but if you get an error or problem just let me know. I don't think there is much overhead with filestreams but if it isn't real fast then try using the read command at the bottom to read it into arrays then compare the arrays instead of the filestreams. If you need to compare different formats or if you are looking for a way to get or set pixels then I know how to do that but it is a little more involved than this since you have to match up pixels and so forth and it requires some knowledge of the bitmap format.

    Public Function CompareFiles(ByVal path1 As String, ByVal path2 As String) As Boolean<br />
        Dim n As Integer, issame As Boolean = True, fstream1 As IO.FileStream, fstream2 As IO.FileStream<br />
<br />
        'create streams<br />
        fstream1 = New IO.FileStream(path1, IO.FileMode.Open, IO.FileAccess.Read)<br />
        fstream2 = New IO.FileStream(path2, IO.FileMode.Open, IO.FileAccess.Read)<br />
<br />
        'compares the streams<br />
        If fstream1.Length = fstream2.Length Then<br />
            For n = 0 To fstream1.Length<br />
                If fstream1.ReadByte <> fstream2.ReadByte Then<br />
                    issame = False<br />
                    Exit For<br />
                End If<br />
            Next<br />
        Else<br />
            issame = False<br />
        End If<br />
<br />
        fstream1.Close()<br />
        fstream2.Close()<br />
<br />
        Return issame<br />
    End Function

The file stream is basically like an array of bytes. You can manipulate any file with file streams and if you want to copy data to or from an array use these commands.

fstream1.Read(yourarray, youroffset, yourcount)<br />
fstream1.Write(yourarray, youroffset, yourcount)

The real $M@22-Dec-07 1:54

Exception for DB connection

22-Dec-07 1:54

Thanks

nishkarsh_k19-Dec-07 21:10

nishkarsh_k

19-Dec-07 21:10

Hello every one

I am developing a VB 2005 Express. At times it happens that the connection to the server breaks. I want to give a option of retry, and connect to the server again

- But even after the network is up then also I am not able to access the server
- Also which is the exact Exception to be used when there is not network connection

Christian Graus19-Dec-07 23:27

Christian Graus

19-Dec-07 23:27

Sounds like you have network issues, not issues in your code.

nishkarsh_k20-Dec-07 7:59

nishkarsh_k

20-Dec-07 7:59

may be that is the case...
but i find the network working for other applications...

i am trying to test the application on network..
I happens that when the network drops due to some reason the application gets stuck..
so i was trying to get a solution like
- stop for some time and try again.
- when i was testing that condition i found even when the network comes back the application is not connecting...

i do not know what to do...

The only way application will work is to restart it, as of now..

What else can i try?

yogesh_kumar_agarwal20-Dec-07 3:16

yogesh_kumar_agarwal

20-Dec-07 3:16

Your problem sounds that you have a application install at one terminal and then you are trying to use the database available on some remote system that could be a system available on LAN.

This error occor due to windows firewall go to the control panel of the server open the window firewall option and turn off it i think it will help you out

With Regards

Yogesh Agarwal