Re: Deleting a textbox control at runtime

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From: Bob Phillips (bob.phillips_at_notheretiscali.co.uk)
Date: 06/12/04 

Date: Sat, 12 Jun 2004 10:17:02 +0100

Even with this 'extra' complexity. does Tom's solution not work okay? His
point about deleting the zeroeth instance is not a best practice but just a
technique that can work well as when a control is deleted, all the others
will shunt down, so the first instance becomes the zeroeth, the second
becomes first, etc. This allows to loop through the controls with a For Each
construct. If you didn't use this technique, you would need to loop
backwards. The problem arises if there are other controls on the page,
because as soon as one of these becomes the zeroeth instance, it never gets
past it (it is always the zeroeth instance from then on).

Hiding/unhding would work just as well here as long as you know the maximum
number. Here is some code with examples of 3 and 5 boxes

Sub HideTextBoxes()
    Dim i As Integer
    Dim ctrl As Control
    Dim objPage As Page
    Const SEARCH_STRING = "txtSprocParam"

    Set objPage = Me.MultiPageKPIs.Pages.Item(1)
    For i = 0 To objPage.Controls.Count - 1
        ' change made here
        Set ctrl = objPage.Controls.Item(i)
        If Left(ctrl.Name, 13) = SEARCH_STRING Then
            ctrl.Visible = False
        End If
    Next i

End Sub

Sub ShowTextBoxes(num As Long)
    Dim i As Integer
    Dim ctrl As Control
    Dim objPage As Page
    Const SEARCH_STRING = "txtSprocParam"

    Set objPage = Me.MultiPageKPIs.Pages.Item(1)
    For i = 0 To objPage.Controls.Count - 1
        ' change made here
        Set ctrl = objPage.Controls.Item(i)
        If Left(ctrl.Name, 13) = SEARCH_STRING Then
            If CLng(Mid(ctrl.Name, 14, 99)) <= num Then
                ctrl.Visible = True
            End If
        End If
    Next i

End Sub

Private Sub CommandButton1_Click()
    HideTextBoxes
    ShowTextBoxes 3
End Sub

Private Sub CommandButton2_Click()
    HideTextBoxes
    ShowTextBoxes 5
End Sub 

-- 
HTH
Bob Phillips
    ... looking out across Poole Harbour to the Purbecks
(remove nothere from the email address if mailing direct)
"Grant Williams" <gwilliams@cockburn.wa.gov.au> wrote in message
news:e30hQkDUEHA.1656@TK2MSFTNGP09.phx.gbl...
>
>
> Thanks for that fellas
>
> Actually the problem may be a little more involved.
> Heres what happens exactly.
>
> The combo box has a list of stored procedures (from an SQL Server 2000
> database).  When I select a stored procedure, I would like to show each
> parameters name and value in a textbox (1 for name and 1 for value).
> Each parameters name and value textbox forms a row (kind of) and for the
> next parameter(s), I increment the Top property of the name and value
> textbox so that the new controls sit below the previous ones.  (do you
> get that - they kind of look like a grid in the end)
>
> If the stored procedure has 10 parameters, I would generate 10 rows (x 2
> textboxes) giving a total of 20 textboxes.
>
> However, if I've made the wrong selection in the combo and re-chose a
> new stored procedure, I need to remove these 20 textboxes that I've
> created (at runtime) and recreate a set of new textboxes which will
> depend on the number of parameters that the newly selected stored
> procedure contains. (possibly 0).
>
> This is why i've created the sub ClearTemporaryControls which can be
> called immediately after selecting the stored procedure but before the
> new controls are created.
>
> One thing you did say Tom was that you always deleted the zeroth indexed
> control.  Is this a rule when deleting controls at runtime or just good
> practice.  Also, if you do delete a control, is the index count
> decremented also and do all controls after the deleted control have
> their indexes decremented likewise?
>
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