Visual Basic

Christian Graus26-Jun-07 18:58

26-Jun-07 18:58

Shared really can't make any difference. The only way I can see for this to happen, is if you call it elsewhere, using these two strings, and they accidentally get concatenated.

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Navneet Hegde26-Jun-07 19:21

Navneet Hegde

26-Jun-07 19:21

Hi ,
Though I don't understand why you want Method to be Shared One
just try this sql ="" before setting sql strconnection.

sql = ""
sql &= "SELECT * FROM tDataEntry"
If strCondition <> "" Then
sql &= " WHERE " & strCondition
End IF

sql &= " ORDER BY DateTime DESC"

Thanks and Wishes
Navneet Hegde
Nashik(City Of Pilgrimage)

Develop2Program & Program2Develop

Christian Graus26-Jun-07 20:19

26-Jun-07 20:19

He wants it to be shared because it has no state, and there's no reason for him to create a class instance, to call it.

Navneet Hegde wrote:
just try this sql ="" before setting sql strconnection.

If that works, it is indicative of a deeper problem, as his code does not concatenate strings, or store them.

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

add form into tab control

Yenyen Suwardy26-Jun-07 20:20

Yenyen Suwardy

26-Jun-07 20:20

Hi,

Thank you for your suggestions. I will try sql = "" as Navneet suggested and monitor the situation to see if the issue happens again.

Cheers!
Yenyen

Phan Van Thao26-Jun-07 17:15

Phan Van Thao

26-Jun-07 17:15

Please tell me how to add form into tab control.
Thanks.

Re: add form into tab control

Christian Graus26-Jun-07 17:48

Re: add form into tab control

26-Jun-07 17:48

You cannot. You can define your form as a user control and host that control in a form, to make a form of it, or in your tab control.

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Phan Van Thao26-Jun-07 22:34

Phan Van Thao

26-Jun-07 22:34

Thanks Christian.

Silly question about calling classes...

commieJerk26-Jun-07 15:27

26-Jun-07 15:27

I have a class that refreshes a datagridview control. I can call this from various places including forms and it works. It is located in a module.

I have a 2nd module with a class that calls the refresh class from the 1st module and for some reason i can do nothing with the data grid view. Msgbox tells me it is going into the refresh class but i cant even set the datagridview.row count to 0.

Example:

module functions
--Public Class DGV

----Public Shared Sub refresh()

Dim dataGV As DataGridView
dataGV = My.Forms.mainWindow.DataGridView1
dataGV.RowCount = 0

----end sub

--end class
end module

module runtime
--Public Class Watcher

----Public Shared Sub Run()

Call DGV.refresh()

----end sub
--end class

end module

Seems so simple but its killing me - from any form (button_click or form_load) it works fine over and over again. I reference it in a 2nd module and the datagrid does nothing... not clearing...

Christian Graus26-Jun-07 15:42

26-Jun-07 15:42

commieJerk wrote:
----Public Shared Sub refresh()

Dim dataGV As DataGridView
dataGV = My.Forms.mainWindow.DataGridView1
dataGV.RowCount = 0

----end sub

This is really nasty. Your code is strongly tied to a specific form, why would you call a dll, just to look for a form, and grab a UI element ( which really shouldn't be public anyhow ), and set a property on it ?

If you have a genuine need to do this in a function, pass the datagridrow into the function.

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

commieJerk26-Jun-07 16:32

26-Jun-07 16:32

ok yea I changed it to Public Shared Sub refresh(ByRef dataGrid As DataGridView).
I am just starting VB - coming from a VBA (access) background so im not used to a lot of basic programming stuff yet cause access does a lot of this stuff for you.

What i am trying to do in a nut shell is - using FileSystemWatcher(), update a datagridview when its change event fires. The problem is doing anything inside the event. I can put stops inside the refresh class and it seems to be clearing the datagridview and reloading the data but it dosent.

When I call the refresh class anywhere elese it works fine?

Christian Graus26-Jun-07 17:47

26-Jun-07 17:47

OK, this is the FileSystemWatcher that's firing an event ? I don't see any reason why code that's run in there would behave any differently. Is that code in a different dll to the main app ? b/c the main problem I'd expect is that you're updating the wrong datagridview - how do you access it ?

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

commieJerk27-Jun-07 1:43

27-Jun-07 1:43

' Add event handlers.
<code>AddHandler watcher.Changed, AddressOf OnChanged</code>
 
' Define the event handlers.
<code>Public Shared Sub OnChanged(ByVal source As Object, ByVal e As FileSystemEventArgs)</code>

  'OnChange gets fired twice for each update so make sure we only do stuff once.
  <code>If bolChanged = False Then
    Call DGV.refresh(My.Forms.mainWindow.DataGridView1)</code>
    'this wont even run -> My.Forms.mainWindow.DataGridView1.rowcount=0
    <code>bolChanged = True
  ElseIf bolChanged = True Then
    bolChanged = False
  End If

End Sub</code>

commieJerk27-Jun-07 1:51

27-Jun-07 1:51

Oh yea and even trying to set the text on a textbox wont work - but msgbox and the console work fine. Is this a limitation of the event sub?

commieJerk28-Jun-07 10:33

check if the date given is within the specific range please help...

28-Jun-07 10:33

Ok i found what i was doing wrong. I didnt realize the FileSystemWatcher event was on the .IO thread and to update a UI I had to use SynchronizingObject = My.Forms.mainWindow to update it. It works great now Smile | :)

cutequencher26-Jun-07 14:32

cutequencher

26-Jun-07 14:32

my problem is i am about to enter new dates:

for example the new date is 6/6/2007 8:15:16
then i need to check if this new date will fall between an existing date...
existing date : 5/6/2007 8:23:54 and 7/6/2007 9:45:10

how could i be able to do that... can you give me a solution... i dont know if there is a predefined function for that...

thnx!

Re: check if the date given is within the specific range please help...

Christian Graus26-Jun-07 15:06

Adding a combobox to a datagridview

26-Jun-07 15:06

The < operator works with DateTime. So create your two range datetimes, and then check if your date > one and < the other. I'd write a helper function to do this.

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

steve_rm26-Jun-07 12:26

steve_rm

26-Jun-07 12:26

Hello

I am trying to add a combo box to a datagridview, using the code below. However, i get the following error message: "Object reference not set to an instance of an object."

I also get this repeated message every few seconds. "The following exception occurred in the datagridview:
system.argumentException: Datagridviewcomboboxcell value is not valid.
To replace this default dialog please handle the dataerror event"

I haven't added the combo to the datagridview at design time, only in the code below.

Try<br />
            'Fill the datagrid<br />
            Me.TA_OrderSoftwarePart_dsCodeRed1.Fill(Me.DsAddComponetAndEquipment.OrderSoftwarePart)<br />
            Me.dgvOrderSoftwarePart.DataSource = Me.bsOrderSoftwarePart<br />
<br />
            Dim dgvc As DataGridViewComboBoxColumn<br />
            dgvc = Me.dgvOrderSoftwarePart.Columns("Status")<br />
<br />
            dgvc.Items.Add("To be Ordered")<br />
            dgvc.Items.Add("Ordered")<br />
            dgvc.Items.Add("Delivered")<br />
<br />
        Catch ex As Exception<br />
            MsgBox(ex.Message)<br />
        End Try

Many thanks for any help with the code above,

Steve

Dave Kreskowiak26-Jun-07 12:34

Re: Adding a combobox to a datagridview [modified]

26-Jun-07 12:34

I only had time for a quick look, but you created a reference to a POSSIBLE DataGridViewComboBoxColumn. You didn't actually create a new column. Change this line:

Dim dgvc As New DataGridViewComboBoxColumn

A guide to posting questions on CodeProject[^]

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

steve_rm26-Jun-07 19:38

steve_rm

26-Jun-07 19:38

Hello,

I didn't use the new key word, as I don't want to create a new column but convert an existing column into a combo box column.

In my database table I have a column called status. This can be either "To be Ordered", "Ordered", or "Delivered".

So when datagridview displays in the form, it will allow the user to select either one of them.

Many thanks,

Steve

-- modified at 1:52 Wednesday 27th June, 2007

Dave Kreskowiak27-Jun-07 2:12

27-Jun-07 2:12

Well, that's where the "Object reference not set to an instance of an object" came from.

If I get your meaning, you can't change the type of the column once it's created. For example, you can't change a TextBoxColumn into a ComboBoxColumn. You can, however, hide the original TextBoxColumn, create an entirely new ComboBoxColumn, add it to the columns collection and setup it's properties to bind to the appropriate column in the dataset.

A guide to posting questions on CodeProject[^]

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

Diane Volk28-Jun-07 10:20

Diane Volk

28-Jun-07 10:20

I've been trying to do the same thing. Could you post code for adding the ComboBoxColumn and binding it to the appropriate column in the dataset?

Thanks,

Diane Volk

Dave Kreskowiak28-Jun-07 18:28

28-Jun-07 18:28

Quick and dirty:

Dim col As New DataGridViewTextBoxColumn()
With col
    .DataPropertyName = "Description"
    .HeaderText = "Description"
End With
DataGridView1.Add(col)

A guide to posting questions on CodeProject[^]

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

Diane Volk29-Jun-07 9:30

Diane Volk

29-Jun-07 9:30

This worked perfectly. I was missing setting the DataPropertyName in my code.

Thanks!

Diane Volk

Search Procedure

wpoopsi26-Jun-07 9:14

wpoopsi

26-Jun-07 9:14

Hello, I'm using Visual Basic 2005. I created html pages inside the webbrowser1 object. I added a text box and search button above the container. I would like the user to put in a word and click the search button to search for that word on the html pages, which are located in the webbrowser1 object container. Can this be done? Does anyone know how? Please help. Confused | :confused:

Re: Search Procedure

Dave Kreskowiak26-Jun-07 10:11