How so suppress the indexchanged event when filling a listbox?

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Hello,

In my code I'm using the SelectedIndexChanged event of listboxes. I had to find out that this event seems to be automatically raised while the listbox gets filled with it's elements.

First of all, after the listbox has been filled I want to have no item selected. I'm currently doing this with "ctrl.SelectedItem = Nothing", but somehow I have the feeling that's not really elegant. Maybe you have a better idea or good practice I can learn on this.

The main concern of my question is: Is there a way to suppress the SelectedIndexChanged event while the listbox hasn't been filled? Which would that be?

Thank you for any hints.

Kind Regards
Michael

What I have tried:

Private Sub lstServers_SelectedIndexChanged(sender As Object, e As System.EventArgs) Handles lstServers.SelectedIndexChanged
      Dim ctrl As ListBox = DirectCast(sender, ListBox)

      ' SelectedItem was set to Nothing beforehand
      If ctrl.SelectedItem IsNot Nothing then
      ... do something ...
      End If
End Sub

Posted 14-Feb-19 7:57am

Sonhospa

Updated 14-Feb-19 8:01am

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OriginalGriff · Accepted Answer · 2019-02-14T08:01:00

Solution 1

You could remove the event from the handlers list and add it back at the end: Add and remove event handlers dynamically in VB.NET[^] That effectively "disables" it while it's being filled.

Posted 14-Feb-19 8:01am

OriginalGriff

Comments

Sonhospa 14-Feb-19 14:45pm

That seems to be exactly what I'm after, thank's a lot! This means I would instantiate the listBox without the "WithEvents" statement, and add the handler later, right?

OriginalGriff 15-Feb-19 2:07am

That would be a lot clearer in the final code, yes.