For Each... statement

16 Mar 2006 7:05 PM

Ronin

group,

please help with the following codes below.

why would this not work... would it require casting/reflecting? if so, does
anyone show me the right codes?

        Dim chk As System.Windows.Forms.CheckBox
        If Not MsgBox("Are you sure you wish to clear?", MsgBoxStyle.YesNo +
MsgBoxStyle.Exclamation, "Clearing") = MsgBoxResult.Yes Then Exit Sub
        For Each ctl In Me.Controls
            If TypeName(ctl) = "GroupBox" Then
                For Each chk In ctl.Controls
                    chk.Checked = False
                Next
            End If
        Next

Please help.

Thanks in advance.

Ronin

16 Mar 2006 8:28 PM

Mattias Sjögren

>why would this not work...

The enumerator returns all controls regardless of the type of your
iteration variable (chk As CheckBox in this case).

You have to do something like

For Each chk As Control In ctl.Controls
If TypeOf chk Is CheckBox Then CType(chk, CheckBox).Checked =False
Next

Mattias

--
Mattias Sjögren [C# MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

16 Mar 2006 9:08 PM

Armin Zingler

Show quote Hide quote

"Ronin" <Ro***@discussions.microsoft.com> schrieb
> group,
>
> please help with the following codes below.
>
> why would this not work... would it require casting/reflecting? if
> so, does anyone show me the right codes?
>
>        Dim chk As System.Windows.Forms.CheckBox
>        If Not MsgBox("Are you sure you wish to clear?",
> MsgBoxStyle.YesNo + MsgBoxStyle.Exclamation, "Clearing") =
> MsgBoxResult.Yes Then Exit Sub
> For Each ctl In Me.Controls
>            If TypeName(ctl) = "GroupBox" Then
>                For Each chk In ctl.Controls
>                    chk.Checked = False
>                Next
>            End If
>        Next

I tried it and it works here.

"Not work" means what? Compile error? Exception? Maybe either the groupbox
is not directly placed on the Form, or not all controls in the Groupbox are
checkboxes. If the latter is the case, use

For Each ctl2 as Control In ctl.Controls
   if typeof ctl2 is Checkbox then
        dim chk as checkbox=directcast(ctl2, checkbox)
        chk.Checked = False
    end if
Next

BTW, I would use

    If typeof ctl is GroupBox

instead, because the compiler would discover a misspelled type name. But
this is not the reason for the problem.

Armin

22 Mar 2006 10:15 AM

Phill W.

"Ronin" <Ro***@discussions.microsoft.com> wrote in message
news:23AEF258-0C81-4713-837E-6825A84B93BF@microsoft.com...

> why would this not work... would it require casting/reflecting? if so,
> does
> anyone show me the right codes?

Something like this :

Option Strict On
Imports System.Windows.Forms

.. . .

If MsgBox("Are you sure you wish to clear?" _
    , MsgBoxStyle.YesNo Or MsgBoxStyle.Question _
    , "Clearing") = MsgBoxResult.Yes _
Then
    For Each possibleGB As Control In Me.Controls
        If TypeOf( possibleGB ) Is GroupBox Then
            For Each possibleCB As Control In ctl.Controls
                If TypeOf( possibleCB ) Is CheckBox Then
                    DirectCast( possibleCB, Checkbox).Checked = False
                End If
            Next
        End If
    Next

End If

HTH,
    Phill W.