Control Arrays

G

Guest

I'm a recent convert to VB.net from VB6...and I can't believe they don't
support control arrays. I have an app that uses a ton of Control
Arrays...mostly labels and text boxes.

I need some guidance on how to proceed...including any third party tools.

Thanks
 
T

Tim Patrick

Try converting your VB6 application to .NET using the Upgrade Wizard built
in to Visual Studio. To use the wizard, just open your VB6 .vbp file with
the "File/Open Project" command in Visual Studio for .NET. Then check the
code in those forms that use control arrays. The wizard uses some custom
classes that try to simulate access in a control-array-like fashion.

If your control arrays exist to support controls that share all logic in
common, you can now share event handlers among multiple controls. This lets
you give unique names to each control, but still use a common event handler.
If the controls in your control array have completely unrelated logic, it
is best to make them distinct controls with unique names, and dispense with
the control array altogether.
 
S

Steve Long

Arne,
I use Tim's approach a lot and it works well. So, you can give your controls
unique names and in code use the AddHandler method to set the method for
whatever event it is you are trying to handle. So, you would write a
function, say TextBox_Click(sender as Object, e as EventArgs)
Then, use the AddHandler method:
AddHandler mytextbox.Click, AddressOf TextBox_Click

Then, in your TextBox_Click routine, you could cast the sender object to a
textbox object and check its name.
So:
Dim myTxt as TextBox
if Typeof sender is TextBox then
myTxt = DirectCast(sender, TextBox)
end if

select case myTxt.Name.ToLower
case "myname"
' do something
case else
' do something else
end select

I wasn't looking at the docs when I wrote this so forgive if I've messed up
an parameters to functions

:)
Steve
 
T

Tim Patrick

Using the name works fine, but you can also test the object itself using
the "Is" keyword to see if it is actually one of your controls.

Public Sub MyTextBoxHandler(ByVal sender As Object, ByVal e As System.EventArgs)
_
Handles TextBox1.TextChanged, TextBox2.TextChanged, TextBox3.TextChanged
If (sender Is TextBox1) Then
' ----- Do text box #1 stuff.
ElseIf (sender Is TextBox2) Then
' ----- Do text box #2 stuff.
ElseIf (sender Is TextBox3) Then
' ----- Do text box #3 stuff.
End If

' ----- Then add common code here.

End Sub

Even though, I think it is generally best to handle each control separately,
and call common routines where there are overlaps.
 

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