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Editorial Team
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Asked: 2026-05-29T05:18:38+00:00

I have an ASP.NET web form on which I’m displaying a list of database

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I have an ASP.NET web form on which I’m displaying a list of database items via user controls, generating the user controls dynamically – working fine.

Also on the page, I have an asp:dropdownlist filled with items that can be added to this database list. Along with this dropdown I have a button ‘ADD’. My intent is that the user chooses and item, clicks add, and then the list of user controls on the form will include this new item.

I have all this working.

My issue is that the user control has a button ‘DELETE’, which removes the selected item from the list. That works, EXCEPT when I add a new item. Because my ‘add’ button event is always fired after Page_Load, even if I regenerate the list of user controls, the internal user control click events won’t fire because the controls weren’t created as part of Page_Load.

I need to know what I’m doing wrong, or best practices here, any advice. I tried to be precise in the description of the problem, but if I’ve not succeeded, let me know and I can add more details.

SIMPLE RESTATE: I need to know how to add a dynamically created user control to a page via a page button click event, and still have the user control internal click(etc) events firing.

Thanks for any help.

EDIT: Based on the feedback from the gentlemen here, and doing some further research related to their suggestions, I ended up implementing a solution based on what’s presented on this page:

http://ryanfarley.com/blog/archive/2005/03/11/1886.aspx

Here’s a snippet showing how I dealt with this. This snippet resides in my PreInit event handler. Not exactly an elegant weapon for a civilized age, but sometimes a blaster is all you’ve got to use.

'Look to see if button for adding a new client number has been
'clicked.  If so, call the sub to add the item NOW, so that it
'is able to have it's internal click events fire.
For Each control_string As String In Request.Form
  Dim ctl As Control = Page.FindControl(control_string)

  If (ctl IsNot Nothing) AndAlso (ctl.ID = "cmdAddClientNumber") Then
    Me.AddClientNumberToList()
    Exit For
  End If
Next
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1 Answer

  1. Editorial Team

    On the button handler, you initially add the UserControl to the Page. OnPreInit (which will next be fired when the user clicks Delete on the UserControl), you should re-add the UserControl – so that it exists, and can handle the Delete button event.

    You will need to devise your own state tracking mechanism to determine that you need to add the UserControl during PreInit. I generally use ViewState, as evidenced by this seemingly similar post.

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