Maybe someone has run across this problem before:

I have an ASP.NET/VB.NET application where a particular user control is giving me some erratic behavior.

The instance of the control that works is first loaded in another user control before it is loaded into the final page.
The instance of the control that doesn't work is simply loaded into the same page as the other embedded instance.
The user control has a drop down list with autopostback set to true. In the embedded instance, the SelectedIndexChanged event handler runs without a problem and passes back the list's SelectedIndex property exactly as it should.
In the instance residing in the page, the SelectedIndexChange event handler never runs and always passes back a SelectedIndex property value of 0, no matter which value I actually select.

Does anything here really jump out at anybody here? Has anybody here experienced something similar? This is driving me nuts at this point...

Thanks,
thanie2001

How are the controls getting into place? Are they in the markup or are you adding them programmatically. Can you post the relevant code?

Here is the registration on the page:

<%@ Register TagPrefix="uc1" TagName="ctlBrowse" Src="ctlBrowse.ascx" %>

And here are the declarations of the objects:
<uc1:ctlbrowse id="ctlBrowseBrand" runat="server"></uc1:ctlbrowse>
<uc1:ctlbrowse id="ctlBrowseModel" runat="server"></uc1:ctlbrowse>
<uc1:ctlbrowse id="ctlDealers" runat="server">

I'm calling the controls programmatically like this:

This is the one that works:
Declaration:
Private WithEvents Dlrs As <projectname>.ctlBrowse
Assignment of variable:
Dlrs = Me.FindControl("ctlDealers")
These assignments are nested one layer deep from the calling page.

These are the ones that don't work:
Declaration:
Private WithEvents oBrands As ctlBrowse
Private WithEvents oModels As ctlBrowse
Assignments:
oBrands = Page.FindControl("ctlbrowseBrand")
oModels = Page.FindControl("ctlBrowseModel")

Here is the declaration of the event handler from the control that fires in the first instance, but not in the other:

Private Sub ItemWasSelected(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddValues.SelectedIndexChanged

Does this help or do you need more?

You shouldn't need to find the controls. Usually the declaration for markup based controls in the codebehind looks like this:

Protected WithEvents ...

Perhaps this is why you are having to FindControl() them. This doesn't explain however why one works and 2 don't.

I don't understand what you mean by "These assignments are nested one layer deep from the calling page."

From what you have so far posted, I am thinking that you want to handle the user control's dropdown changed event on the page. Is this correct? If so, then you need to do this a different way. You should create a public event on the user control, and raise this event in the event handler of the dropdown. Then the page will handle the user control's event that you raised.

Look about half way down this thread for a cheesy little drawing of mine that shows event bubbling.

Peter
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