Accessing Controls Located in a GroupBox

I'm fairly new at this, so please bear with me. I am trying to reset the background of text boxes that are located within different groupboxes. The code I am using is as follows:

Private Function ResetBackGround(ByVal form As System.Object)
        For Each ctrl As Control In form.Controls
            If ctrl.GetType.Name = "TextBox" Then
                ctrl.BackColor = Color.White
            End If
        Next
    End Function

Called by:
ResetBackGround(Form1.ActiveForm)

The function will reset any textbox on the form not part of a groupbox. I've tried various code variations in an attempt to access the textboxes in the groups, but no luck. Any help would be greatly appreciated.

Thanks,
Bret

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Accessing Controls Located in a GroupBox

jaypee68
The original method you posted only looks through one object's controls collection. So it tests each control in the given form's controls collection. The routine only tests for textboxes and set's their backcolor. The groupboxes you are using have their own controls collection that contain more textboxes. These textboxes do not exist in the controlls collection of the form that contains the groupbox so they are not found by the routine.

Using recursion allows the method to test each control in a given controls collection and then test the controls within <i>that</i> control's controls collection.

Think of it like looking for folders on your hard drive. If passed the folder "C:\Windows", your loop would only find the folders directly under c:\windows like c:\windows\system and c:\windows\system32. It would not find the subfolders within those folders; such as c:\windows\system32\Microsoft. But using recursion, the sub looks for all folders within the given folder "c:\windows" and then calls itself, passing each folder it finds in c:\windows. This contiunes in turn until no folders are found. The current loop then ends and the routine starts over with the next element of the previous level.

Make sense
Chips_in
Thanks, that did the trick!

I'm curious though why a recursive sub had to be used. Why wouldn't my original method of using the "For Each ctrl" statement work

Thanks again,
BDS
Vishantha
Use a recursive sub something like:

    Private Sub ResetAllBackgrounds(ByVal ctl As Control)
        If ctl.GetType Is GetType(TextBox) Then
            ctl.BackColor = Color.White
        End If
        For Each c As Control In ctl.Controls
            If c.GetType Is GetType(TextBox) Then
                c.BackColor = Color.White
            End If
            ResetAllBackgrounds(c)
        Next
    End Sub

Then call this sub in your loop:

Private Function ResetBackGround(ByVal form As System.Object)
For Each ctrl As Control In form.Controls
    ResetAllBackgrounds(ctrl)
Next
End Function

Note that your function should really be a subroutine since it does not return a value.

HTH
Accessing Controls Located in a GroupBox

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