Visual Basic

Dave Kreskowiak10-Oct-08 5:14

10-Oct-08 5:14

No, it's not. All drawing happens on the UI thread, no matter what.

I thought you said you moved the long-running operation to a seperate thread and left the Scrolling Text on the UI thread.

Basically, since you have no source code or control over the control that's loading the move, it's going to do it's operation on the UI thread, no matter what you do. The only option you have is to find a control that loads it's data in it's own background thread. I don't know of any off the top of my head.

Basically, you have to get each operation you want running at the same time in it's own thread. All rendering will happen on the UI thread, no matter what. So, if any operation, like loading the movie, happens on the UI thread, all drawing for all other controls, no matter what thread they're on, will stop, until the movie is loaded.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008

ambio12-Oct-08 22:34

ambio

12-Oct-08 22:34

I'm using the webbrowser control of Microsoft to load a HTML page. When I use this control to load a page, the most of the controls are waiting then for a short time. So this means that the webbrowser control is doing his work in the UI thread? If so, why it's implemented in this way? I think it should be better to do the work of the webbrowser in a seperate thread.

Dave Kreskowiak13-Oct-08 1:27

13-Oct-08 1:27

ambio wrote:
When I use this control to load a page, the most of the controls are waiting then for a short time. So this means that the webbrowser control is doing his work in the UI thread?

Yes.

ambio wrote:
If so, why it's implemented in this way?

Ask Microsoft.

ambio wrote:
I think it should be better to do the work of the webbrowser in a seperate thread.

The WebBrwoser control is an implementation of Internet Explorer, NOT a "from the ground up" purpose built browser control. Your constrained by the limits of IE.

If you want true multithreading, you'll have to write the page downloading stuff yourself. Check into the HttpWebRequest class.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008

ambio13-Oct-08 2:13

ambio

13-Oct-08 2:13

Ok, thanks for your help and time.

Transaction AS400

helelark1239-Oct-08 20:32

helelark123

9-Oct-08 20:32

Hello,

Is it possible to use vb.net transactions with connection to AS400?
Here is a snippet:

objConn.Open()

' Make the transaction.
Dim trans As Odbc.OdbcTransaction = _
objConn.BeginTransaction(IsolationLevel.ReadCommitted)

' Make a Command for this connection
' and this transaction.
Dim cmd As New Odbc.OdbcCommand( _
"UPDATE AUTCTRL SET CTLNM=? WHERE CTLNM=?", _
objConn, _
trans)

' Create parameters for the first command.
cmd.Parameters.Add(New Odbc.OdbcParameter("CTLNM", txtFirstName1.Text))
cmd.Parameters.Add(New Odbc.OdbcParameter("CTLNM", txtLastName1.Text))

' Execute the second command.
cmd.ExecuteNonQuery() '(1) BUG IN THIS LINE

' Create parameters for the second command.
cmd.Parameters.Clear()
cmd.Parameters.Add(New OleDb.OleDbParameter("CTLNM", txtFirstName2.Text))
cmd.Parameters.Add(New OleDb.OleDbParameter("CTLNM", txtLastName2.Text))

' Execute the second command.
cmd.ExecuteNonQuery()

' Commit the transaction.
trans.Commit()

' Close the connection.
objConn.Close()

'(1): ERROR [HY000] [IBM][Client Access Express ODBC Driver (32-bit)][DB2/400 SQL]SQL7008 - AUTCTRL in RAVONLIBT not valid for operation.

Thank you

Shay Noy

Ashfield9-Oct-08 21:34

Ashfield

9-Oct-08 21:34

As far as I know, AS400 is a type of IBM computer, not a database. I assume you have a database on there (as you have a connection), so I expect the database either supports these types of transactions or, by the error message, more likely it doesn't. In a nutshell, check your database documentation.

Hope this helps

Bob
Ashfield Consultants Ltd

Mycroft Holmes9-Oct-08 21:41

Mycroft Holmes

9-Oct-08 21:41

I wonder if it is DB2. The only time I used AS400 stuff it was a cobol type environment I think but that was in the 90's.

Never underestimate the power of human stupidity
RAH

Wendelius10-Oct-08 7:01

Wendelius

10-Oct-08 7:01

It's DB2.

The need to optimize rises from a bad design

Kschuler10-Oct-08 6:41

Kschuler

10-Oct-08 6:41

Try this[^].

Or try a google search[^].

Hope this helps.

Sockets, remoting or web services which one to use?

Wendelius10-Oct-08 7:59

Wendelius

10-Oct-08 7:59

Have a look at this: Error SQL7008 while updating a DB2/400 table[^]

The need to optimize rises from a bad design

rprateek9-Oct-08 13:08

rprateek

9-Oct-08 13:08

Hi all,

I am about to develop a client server application in which there can be more than 2000 clients continuously using the application at once.

The rows returned at one time might be of 1000 s as well. Previously in VB 6 I use to use win sock or dart sock for communicating but the projects were not as big as this.

Now i am developing this application in .net 2005 and i went through web and found 3 different approaches of communicating between client and server applications and so I am not being able to choose the right one for me.

In my application i will have one desktop application and one web application. Both of these interfaces can be used by clients which connect to remote server and i need to log the connected users as well.
Then server will process the requests and talk to Active x objects which will be located in different remote location and those active x objects will talk to database and get back the rows and have to return to appropriate client.

Ok now in this scenario what would be better for me to use? please advice advantages and disadvantages of using each of the processes.

thanks in advance

Blog for Programmers

Re: Sockets, remoting or web services which one to use?

Mycroft Holmes9-Oct-08 21:46

Mycroft Holmes

9-Oct-08 21:46

I would probably use a web service. I beleive remoting will give you a faster response but the environment is more complex to maintain. I'll be interested in other responses.

Never underestimate the power of human stupidity
RAH

Retrieve a large number of filenames

Sonhospa9-Oct-08 8:57

9-Oct-08 8:57

Hello to all you gurus and supporters here!

I seem to create some performance trouble when it comes to reading the filenames from a large directory (~ 30 thousand files) into a listview field like that:

Dim TargetFileList As Array

With openDLG
    ...
    If .ShowDialog = Windows.Forms.DialogResult.OK Then
        TargetFileList = openDLG.FileNames
        Return TargetFileList
    End if
End With

The applications dialog window freezes for long... long....

Does someone of you probably know a better (i.e. faster) way of reading all of these filenames? The purpose is to find similar names in another directory and display filesInDir1 / missing files / filesInDir2 in different listview fields then.

Thank you for any inspiration D'Oh! | :doh:

Michael

Dave Kreskowiak9-Oct-08 9:26

9-Oct-08 9:26

There's no way to speed this up. You're already using the system supplied dialog. Really, the problem is in returning a list of 30,000+ filenames and rendering them in the dialog. You'll ahve to write your own, but I doubt you'll see any performance gains that would justify the effort.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008

Wendelius9-Oct-08 9:27

Wendelius

9-Oct-08 9:27

Listview doesn't handle that much items very fast in normal mode. Have a look at ListView.VirtualMode Property[^]

The need to optimize rises from a bad design

Sonhospa9-Oct-08 20:24

9-Oct-08 20:24

Thank you both for examining.
I'll have a close look at the VirtualMode.

Jon_Boy10-Oct-08 4:26

Jon_Boy

10-Oct-08 4:26

I had to do something similar to what your trying to accomplish. Basically I have a treeview that is being 'partially' built with dirs/filenames when the app loads. The app requirements were that some directories were to be selected by default meaning that the "parent" directory, sub dirs, and all files are to be selected. The user can also select just a dir or selected files (so I used a tri-state checkbox scheme with the grid lines).

If a parent is expanded, the files and dirs are then populated. If closed and checked, there's no need to pull the files since you're selecting everything unless the users expands the node (if this is making sense).

We have dirs with a very large amount of files per folder. Trying to pull all file names for all folders at once could be done. Had to split it out a little.

Any suggestions, ideas, or 'constructive criticism' are always welcome.

Sonhospa10-Oct-08 8:01

Is BrowseForFolder gone in the new VB?

10-Oct-08 8:01

Smart idea, kissdnuts - guess you had some good coffee again Wink | ;)

! I thought it might be the shorter and faster way to use standard windows dialogs, but it seems the standard dialog collects the files already when a folder has been selected (which doesn't make a lot of sense, does it?).

Would you be so kind Rose | [Rose]

as to put some example code for populating the tree view?

Thanks
Michael

Sonhospa9-Oct-08 8:38

9-Oct-08 8:38

Hi everybody,

gotta deal with directories containing large numbers of files (approx. 30.000 in each dir), so that directory selection seems to be an endless process ( Sleepy | :zzz:

pita

) for the user if I use the the VB 2008 (Express) FolderBrowserDialog object.

In an older VBScript solution I was able to integrate a text field into the shell.BrowseForFolder object (parameter), so that there was the option to type or paste a path alternatively. This option I can't find for the FolderBrowserDialog, nor can I find any information if (and Wink | ;)

if not: how?) it's possible to use the shell.BrowseForFolder in VB 2008.

Does someone of you know a nice & fast solution for selecting a folder containing so many files? I don't need any filenames here, just the path.

Thank you
Michael

Jon_Boy9-Oct-08 9:07

Jon_Boy

9-Oct-08 9:07

I did something similar to what your doing. I used a treeview/listview with checkboxes so that the user could select directories etc dynamically.

Any suggestions, ideas, or 'constructive criticism' are always welcome.

Dave Doknjas9-Oct-08 12:55

Dave Doknjas

9-Oct-08 12:55

You can use the "FolderBrowserDialog" class in System.Windows.Forms.

David Anton
http://www.tangiblesoftwaresolutions.com
C++ to C# Converter
C++ to VB Converter
C++ to Java Converter
VB & C# to Java Converter
Java to VB & C# Converter
Instant C#: VB to C# converter
Instant VB: C# to VB converter
Instant C++: convert VB, C#, or Java to C++/CLI

Sonhospa10-Oct-08 8:03

10-Oct-08 8:03

Thank you both for inspiration. I'll check it out!

Sonhospa10-Oct-08 12:26

Extract binary resources [modified]

10-Oct-08 12:26

Thanks for your answer, but are there really different objects called "FolderBrowserDialog"?

I had used the one "FolderBrowserDialog" before, like

Dim openFLD As New FolderBrowserDialog

and that's the one that takes endless time and makes the application freeze with a large file number.

In case there are different objects of the same name: HOW would I tell VB which one to use?

Regards
Michael

mastergamer01689-Oct-08 8:16

mastergamer0168

9-Oct-08 8:16

I've added a binary file to my project as a resource, and set it's Build Action to Embedded Resource. How can I read the data and save it into an output file when the user clicks a button?

modified on Thursday, October 9, 2008 2:36 PM

Re: Extract binary resources

Dave Kreskowiak10-Oct-08 5:05