[resolved] Dynamic controls disappear on click

[MrGTI]

This is probably a simple solution, but i can't figure it out......

I dynamically create a control on the page, but it disappears when a button on the page is clicked. Here's an example of what i have:

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'If Me.IsPostBack = True Then Exit Sub
    End Sub
 
    Private Sub btnOne_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOne.Click
        Dim chkSample As New CheckBox
        With chkSample
            .Text = "I was added in the code"
            .ID = "chkSample"
            .EnableViewState = True
        End With
 
        pnlSample.Controls.Clear()
        pnlSample.Controls.Add(chkSample)
        pnlSample.EnableViewState = True
 
        lblTalk.Text = "button ONE was clicked"
    End Sub
 
    Private Sub btnTwo_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnTwo.Click
        lblTalk.Text = "button TWO was clicked"
    End Sub

I thought that the controls and their state were supposed to remain, but they don't. Run the page and click the first button - the code runs and creates the checkbox. Then click the second button - the checkbox vanishes.

What am i doing wrong?

[basilisk]

Dynamically added controls need to be readded at every postback. This article explains the ins and outs:
http://msdn.microsoft.com/library/de.../viewstate.asp

(there is a section in it about dynamically added controls)

The following is on Denis Bauer site as he has created a custom control that recreates dynamic controls on postbacks:
http://www.denisbauer.com/ASPNETCont...aceholder.aspx

i hope this helps

[VBKNIGHT]

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Me.IsPostBack Then
call btnOne_Click
end if
End Sub

Private Sub btnOne_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOne.Click
Dim chkSample As New CheckBox
With chkSample
.Text = "I was added in the code"
.ID = "chkSample"
.EnableViewState = True
End With

pnlSample.Controls.Clear()
pnlSample.Controls.Add(chkSample)
pnlSample.EnableViewState = True

lblTalk.Text = "button ONE was clicked"
End Sub

Private Sub btnTwo_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnTwo.Click
lblTalk.Text = "button TWO was clicked"
End Sub

[VBKNIGHT]

well that one wont work..u should initialize every object every postback i guess

[MrGTI]

Thanks guys.

I read that huge article basilisk. I'm very disappointed that ASP.NET does not retain the dynamically added controls. It looks like a very big oversight on their part.

I will try out that control by Denis Bauer. It certainly looks like it will do the job. I just wish it wasn't needed.

[MrGTI]

The control created by Denis Bauer (DynamicControlsPlaceholder) worked great.