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I guess that there is more text in the item than will fit in the ListView? You could consider shortening the text in the ListViewItem, or use owner-drawing 
I are troll
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Thanks Eddy..
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Hi to all Experts,
I have a MS access database (.mdb) in a server, which I am going to access from several clients( VB application )(for each clients the operation are just opening it reading/updating it, and closing it quickly).
So, when i access it simultaneously, i wonder,
1. is there any chances my database will crash?, If so, what is the solution to avoid it?
2. or does MS access has its own solution to concurrency problem or does it have any locking mechanism, to avoid crashing?
Thanks in advance :
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Member 4250705 wrote: 1. is there any chances my database will crash?, If so, what is the solution to avoid it?
There is no chance of system crash.
Member 4250705 wrote: or does MS access has its own solution to concurrency problem or does it have any locking mechanism, to avoid crashing?
MS Access has it own locking mechanism
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thanks aman,
So I need not to think for any synchronization or locking mechanism right?
Also could you please tell me, what about the running a single file(ppt) as like the same above, ie. am trying to run a ppt file from all client simultaneously using new processes for all of them separately ie
on buttonClick i wrote the following code::
dim p as process
p.startinfo.filename="//server/c:/path/filename.ppt"
p.start()
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Member 4250705 wrote: So I need not to think for any synchronization or locking mechanism right?
Depends if you are using a disconnected DataSet or not. If you are then you will need to handle updates in some form or other.
Access will only lock the record for as long as the connection remainds open.
Member 4250705 wrote: p.startinfo.filename="//server/c:/path/filename.ppt"
The file path is wrong, but the logic is sound.
Steve Jowett
-------------------------
Real programmers don't comment their code. If it was hard to write, it should be hard to read.
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Member 4250705 wrote: 1. is there any chances my database will crash?, If so, what is the solution to avoid it?
There is no easy solution. If there were, Microsoft would have added it to Access itself. Your database will not crash, but data may be lost.
Member 4250705 wrote: 2. or does MS access has its own solution to concurrency problem or does it have any locking mechanism, to avoid crashing?
Access is not a server-technology. I believe that Access uses optimistic locking, and it gets very slow once there's a lot of data.
You can easily upgrade your MS-Access database to a complete SQL-Server database. There's a free version of SQL Server called "SQL Server Express", and you can use the Wizard in Access to convert your database to a "real" server-database.
Hope this helps,
I are troll
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Member 4250705 wrote: is there any chances my database will crash?, If so, what is the solution to avoid it
The database won't crash if it's used simultaneously. It's designed for that. One possible reason when Access db could crash is that you have several clients using the database with different versions of drivers (odbc, jet, whatever you use). Sometimes different versions are not compatible with each other and this can lead to problems and corruptions.
Also the database itself cannot crash since there actually is no true database, just a file and a driver at client side. But still the file may corrupt.
Member 4250705 wrote: or does MS access has its own solution to concurrency problem or does it have any locking mechanism, to avoid crashing
Again no crashing will occur if several users update the same data. When exactly the same data is updated by 2 users at the same time, the first one who finishes the operation gets his data into the database and the second one gets an error message to the client saying that someone has already modified the data. This behaviour happens if the record locking is set to No locks (optimistic).
If the record locking is set to Edited records, then pessimistic locking is used. Now with the same example if the first user starts to edit the row, the second user cannot edit the row until the first one has finished the operation.
As Eddy Vluggen said, you can migrate to SQL Server Express Edition in order to use a true relational database instead of a 'flat-file' storage (Access). For more info: http://www.microsoft.com/express/sql/default.aspx[^]
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guys,
Sincere thanks to all of you for your valuable reply.
Thanks a lot again
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Hi All,
How can i hide process of my application from Task manager.
Pls help it's needful.
Thanks
Anubhava Dimri
mailto: anubhava.prodata@gmail.com
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The answer hasn't changed since you asked this the last time.
Despite everything, the person most likely to be fooling you next is yourself.
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I guess you can use showInTaskbar method
eg:
to hide a form,
me.showInTaskbar=false
I think that will work fine
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I am saying abount Process of Application not about Application Task.
mailto: anubhava.prodata@gmail.com
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Hi,
I have tried this n VB (not in .net) by taking a help of an article on code guru , follow the link for the article
http://www.codeguru.com/forum/showthread.php?t=406555[^]
I worked in my case , hope this helps you too.
-Regards
Bharat Jain
bharat.jain.nagpur@gmail.com
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Excuse me, but that doesn't hide your process from Task Manager. It just STOPS Task Manager from updating it's list and disables the options to unpause it.
Now, think about this. What possible legitimate use does this have??
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None, but this is going to cause a string of questionable questions from this user now that he has this snippet of code.
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Hi to All,
Here I come with another problem.
I am using Crystal Report with VB.NET 2005. Now, I have a MS ACCESS database ( which will be in a fixed folder say (c:\Mydatabase\aa.mdb). To deploy my project, I need to load the paths of the report dynamically. My connection String for the project wont be having any problem, since my path to the database is fixed.
For my Crystal Report, what are the consideration I should make, so that after installing my project in any machine, it should work ( NOTE that I will copy the database in the same path).
Do I have to copy the xx.rpt to any specific folder while deploying? What will be the string path look like then?
Please help me with all the details.
Regards,
Himangshu
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Hi,
At the time of report generation you can set the path of Crystal Report which you want.
Example are given below.
Dim rpt As CRAXDRT.Report
rpt = crx.OpenReport(application.startuppath & "\Report3.rpt")
mailto: anubhava.prodata@gmail.com
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thax for the reply,. So should I copy the report file also to the bin folder before the set up creation?
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Good Morning
I have a query related to DLINQ. I have a datagridview with a combo box in the one field. The user may select categories from the drop down box.
Only one category can exist (no duplicates). What I want to do is using LINQ to get a new dataset containing all the records that is not selected (by the datagridview) and the value of the current selected one and gives that as a datasource for the combo box.
This way the user doesn’t have multiple options that they shouldn’t select anyway but only the ones they can select.
I have problems defining a query to get the data. Has anyone tried doing this before?
I have played around and this is what I have currently but it doesn't include the current row aswell.
(I am new to LINQ and don't understand the full meaning of the queries - any one can translate it in normal word will great  - The code snippet below is by looking at examples)
Dim query = From t1 In dataset1.tblLookup.AsEnumerable() _
Group Join r In dataset2.tblMainDisplayDGV.AsEnumerable() _
On r.Field(Of String)("CommonField") Equals t1.Field(Of String)("CommonField") _
Into x = Group _
From r2 In x.DefaultIfEmpty() _
Where r2 Is Nothing _
Select t1
Regards,
Christiaan
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hello this thread is a little old...sorry had to revive it..as i haven't yet found a solution...
the name if the thread is 'How to update form control from an embedded form'
I have two forms,one is added as a control to another an I need to update a listbox in parent from the child form.
This code is in the parent form,I have added this in the form load event of the parent form
Dim obj1 As New childform
AddHandler obj1.addtolist, AddressOf addtolistbox
and this is sub that is subscribed to the event..
Private Sub addtolistbox(ByVal str As String)
ListBox1.Items.Add(str)
End Sub
In the child form....
Public Event addtolist(ByVal s As String)
and in the sub where I want to add to listbox in parent form,
RaiseEvent addtolist(ds1.Tables(0).Rows(0)("Reader_location").ToString & " Connected ")
I have tried this and it doesnt work,the debugger just goes to next line.Can't understand why.
The code of the parent form has some BGW threads.Infact the child form is invoked from the BGW.Is this a problem?
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Don't start a new thread. Keep responding to the same thread so people can see what'sbeen going on.
Sohaib_A wrote: The code of the parent form has some BGW threads.Infact the child form is invoked from the BGW.Is this a problem?
Great! NOW you mention the child form is on a background thread. First, this is a bad idea. ALL GUI objects (forms included) should only be created on the UI thread. Any work that needs to be done can go on a seperate thread.
Since the BGW is NOW the case, what you've been told is not going to work. You cannot modify controls created on the UI from another thread. You can pretty much scrap half of the things you were told and start looking into the ReportProgress method of the BGW. This is pretty much going to be the easiest method of getting periodically generated data out of the code that the BGW is running. You're looking for this[^] version of the method.
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Ok..so I got it to work.Had to get rid of the BGW.You were right,they were a bad idea.But i wonder why I wasn't getting any cross-threading errors.
Actually what i was trying to do is,I have a snippet code in which there are several API calls for a certain hardware device and the data that i get from this device has to be dispayed on a form and also manipulated in a database.
I want to run several instances of this code at the same time as I have more than device running at the same time performing the same operation.Also the devices will perform this operation at specific intervals.
Currently I am doing this using timers for the operation interval and lists for the multiple forms.All these forms are added as control to a parent form.
I want to try to get this to work using threading,i:e; each 'device' or instance would be running in its own thread.And all the threads would be running and instance of the code in parallel.
I tried using BGW lists to create forms and run the code,but there were many complications one of which you know.
I don't know much about threading as i haven't done it before,all I know is stuff I've read online.
My questions are
1.As threading is known to improve performance and response of an application,will it do the same in this case or just make it more complicated and slower?
2.If threading is the way to go,will there be issues of thread synchronization and can all these threads run in parallel?
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Hello I want to add a Checklistbox in Datagridview in vb.net.
How can i do this?
Pls help me.
Thanks in advance
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did you mean you want a checkbox column on you datagridview?
if you mean this, you can create a checkbox column in two ways:
1-create a template column and insert a checkbox control on it
2-your datasource field have a boolean/bit type
Human knowledge belongs to the world
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