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I’m trying to drag & drop listview items between two instances of my app. The actual data that’s passed in DoDragDrop is an arraylist that’s been serialized to a memorystream. The contents of the arraylist are objects of a simple, serializable custom class that allows the recipient listview to reconstruct the dragged listitems. (the contents of the arraylist actually don’t matter…they can be simple integers and the issues in this post remain the same)
When I’m dragging & dropping within an instance of my app, e.Data from the DragDrop event is a DataObject and I can extract my memorystream, deserialize it, and I’m good. However, when I drag & drop to another instance of my application, e.Data is a System.__ComObject. Attempting to extract my data with the normal e.Data.GetData method results in a memorystream that’s, according to the Locals window, a System.Runtime.Remoting.Proxies.__TransparentProxy, which is beyond the scope of my VB knowledge. Regardless, it doesn’t deserialize, and now I’m stuck.
So could someone kindly explain what I need to do to the __ComObject to get my memorystream out? Here’s my code:
If e.Data.GetDataPresent("System.IO.MemoryStream") Then
Dim Formatter As New BinaryFormatter
Dim Stream As New System.IO.MemoryStream
Dim DropList As New ArrayList
Stream = e.Data.GetData("System.IO.MemoryStream")
Stream.Position = 0
DropList = Formatter.Deserialize(Stream)
Any help would be appreciated.
Neil
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I am trying to create a program for my company which will create new folders for incoming employees. This folder needs to be created and the sharing permissions need to be set programmatically (VB.NET). I know how to create the folder, but setting the permissions is posing a problem. If anyone has any advice on the matter, I would greatly appreciate it.
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The .NET Framework BCL (1.0 and 1.1) don't have any support for doing this. The .NET Framework 2.0 does.
In the mean time, you can use a class library found here[^] on GotDotNet to do this.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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Somewhere in the past couple years I heard that VB.Net has something built in that will copy a SQL Server table(including schema) to a file. Now that I want to use it, of course I can't find anything on it. Anyone familiar with this?
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Could you be referring to the DataSet class' ability to save to an XML file?
DataSet.WriteXML()[^] method docs.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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I just want to have an idea on how can I read the data from a time-tracking device (everytime an employee swipes his ID card) and be automatically copied into a backend Access database of my VB.NET program. What should be the coding for that? I really can't imagine how and what code should I write in my VB.NET program to get data from the device shoot into my database. And not only that, the device is not directly connected to HR's PC but connected through the LAN network.Can anyone help me regarding this matter?...Please...Thanks...
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The easy part is putting the data into the database.
The hard part is getting a notification from the "device" and communicating with it. Without knowing anything more about the "device", it's impossible to tell you anything useful, other than consult with the manuals and manufacturer of the "device" to find out what you have to do.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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Hi,
I'm developing an WinForms application in VB.NET where the user can specify custom formats for numeric data entry fields.
When I display data in lists, labels, editboxes, etc. I simply use Double.Format(strCustomFormat) to format the double values in the desired format - no problem here.
But I'm having a problem converting the strings back to a double since I basicly don't know if the user is using a 1.234.567,09 or 1,234,567.09 format.
So basicly I need a Double.Parse method where I can specify the format (similar to the ParseExact that DateTime has)... but this is not available as standard for Doubles 
Is there any other way I can do this ?
Thanks you in advance.
/Bean
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Hi,
Use string replace(",","") method for removing , commas
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Please read my thread again... it's far more complicated than that; a simple "," replace/removal won't do the job.
For example... does "100,123" mean 100.123 or 100123.00 ... it's impossible to tell without actually knowing the format.
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This is a complicated task especially since you are giving your user the freedom of customizing the formats. Like you have said:
MrBean wrote:
it's impossible to tell without actually knowing the format
Therefore, I would suggest giving your user a list of choices. That way you can create your Double.Parse function according to the formats that you have allowed the user the choose from.
I would suggest giving your user full freedom of specifying formats is a bad idea, especially when dealing with data.
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Hi there,
I see the problem ur facing I had a similar one.You can do this little trick and I think the problem Should slove
you basically have two formats here
1) 1.235.567,09
2) 1,234,567.09
To what I have understood,If format 1 is used there would be only one comma in the string and if format 2 is used there will be only single decimal
So now you can parse the string and check how many decimals or commas exists in a string if decimals are more than one remove decimals and if commas are more than one remove commas.
Now the question if what if there is only one comma and one decimal in the string. then Whatever comes first remove that and you should be good
Hope this helps
Let me know abt it
Mandar Patankar
Microsoft Certified professional
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My current solution (which is not 100%) works a lot like you describes : detects which comes first, "," or "."
But the case where there are no decimals but thousand delimiters... example :
123,456
It impossible to know if this means 123.456 or 12345.00 without knowing the input format.
I was just wondering if there was a ".NET way" of converting strings back to doubles and specifying a format string which the parser should use... just like the ParseExact which the Date type supports just fine. It seems this is a big oversight from the .NET team.
Unfortunately I can't limit the formats the users can enter to a predefined set - the users expect full freedom here and the old (non-.NET) version of the app had this functionality
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hye .. your problem looks very critical. well if you have the mask for the format which user is using then it is fine like ##,##,##.00 or ##.##.##,00
then you can see which option is decimal like in first . represents decimal and in next , represents decimal. but if this is not the case and you dont have the mask then tell me what is this
12,0 $ and 12.0 $ .. you have to tell me which one is 120 $ and which one is 12 $.
now you cannot even visually tell which one is what and believe me I shall go opposite to your answer  .So restrict your user to one mask other wise you will end up with a big money theft in company account.
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Dear Friends,
I have installed my VB6 application package on the machines in my lan. But when I open the crystal report file it gives error like "No physical database found". Your quick response will be highly appreciated.
thanks
Murtuza
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More details would be helpful in diagnosing this problem. Possibly this is a Crystal config/parameter issue? Where is the target file for Crystal located?
...Steve
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Dear Steve
Thanks For help.
I am using MS Access as database and the .rpt files i m including in the package and it is installed on evry machine in c:\program files app folder. for file i am using the ODBC connectivity. and iside vb code i am using app.path to get the file path to display file on crystal viewer control.
thanks
murtuza
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Murtuza,
I understand that you have an Access database and Crystal RPT files installed on each machine, and that these are all in the App.Path. Correct? Are you sure that the ODBC DSN is setup correctly on each workstation? Can you show us the code that you are using to load the file into the control?
...Steve
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Dear Steve
the code to insert rpt file is as below
Option Explicit
Dim oApp As New CRAXDRT.Application
Dim oReport As New CRAXDRT.Report
Private Sub Form_Load()
Set oReport = oApp.OpenReport(app.Path & "\SalesRep.rpt", 0)
oReport.SQLQueryString = StockSql
CRViewer1.ReportSource = oReport
CRViewer1.ViewReport
End Sub
the database is on server machine only and i am using DSN to connect client program with server the othr forms are working fine except crystal report files. the error is coming"no physical database found"
thanks
Murtuza
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Are the reports stand alone or are you passing the path to the database to the reports in your code. Its a bit hard with the limited information you have provided to know whatyour problem is. In general if you create the report on your PC against a database in for example the c:\mydatabase folder or against and ODBC datasource called MyData then when you put the report on another PC it will still expect the database to be in a folder called c:\mydatabase or to have the ODBC datasource MyData set up. If not then you can either pass this information to the report from within your code or use 'Set Location' from the menu in Crystal reports to make the report look at the correct database location.
I am assuming a situation like the database is on one PC and other 'Client' PCs connect to it.
Jon
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Dear Steve
the code to insert rpt file is as below
Option Explicit
Dim oApp As New CRAXDRT.Application
Dim oReport As New CRAXDRT.Report
Private Sub Form_Load()
Set oReport = oApp.OpenReport(app.Path & "\SalesRep.rpt", 0)
oReport.SQLQueryString = StockSql
CRViewer1.ReportSource = oReport
CRViewer1.ViewReport
End Sub
the database is on server machine only and i am using DSN to connect client program with server the othr forms are working fine except crystal report files. the error is coming"no physical database found"
thanks
Murtuza
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hello Murtaza
It was around 6 months back when I was working on Crystal and I had this problem. to be very honest I forgot what I did with that to solve. But I do remember it was some very small issue in that program. So go and re check your report. like in crystal open report and check in File menu .. that data should not be saved in the report. some times it creates a problem. if you are totally stuck then do one more thing. build a simple report which has nothing instead of time stamp on it and check it on client. so that if it loads then problem is in DSN and if dont then problem in Crystal report missing required files.
Best of luck and do remind me the solution. + let me know your crystal version
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Hi guys,
i'm currently developing an application that will be sending data out over the web.
To enchance the users experience of this application i have decided that it would be good to send all of the data in the background of the application while the user continues to use the application.
The scenario:
A user adds a record in the application.
Application sends the data to a web service
Web service adds a record to a database and returns the ID of that new record
User continues to add new details to this newly created record inside the application
Application keeps track of newly created ID and whenever the user decides to update this record a new thread is spawned and updates the record in the database (using a SQL update statement on the returned ID from the webservice).
Problem is, that sometimes the user can add things too quickly to the record and the web service hasn't returned an ID...this means we can't update the record (as we have no ID).
What i want to know, is how do i make sure that the initial thread has finished processing and has returned some data so that the next thread can continue on and update the record?
Thanks
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You will always have some latency with any web service and you'll probably need to synchronize the initial record creation with the rest of your program.
Briefly, create a global synchronization object (either a mutex or semaphore) which the main thread can interrogate whether or not a new ID is ready for use. The child thread will set this object to True when it is done indicating that the main program can update this record. If False or not set, then record updating cannot occur.
You'll also need to cater for a non-response or timeout from the web service. A better idea may be to (additionally) cache the data on the client until (when or if) the web service responds and is capable of handling the updates.
...Steve
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