VB.NET - Iterating through controls in a container object

Question

I have a form with a \"Clear\" button.

When the user clicks \"Clear\", I want to clear the value of all the visible elements on the form. In the case of date contro

Answer 1

For Each c In CONTAINER.Controls
    If TypeOf c Is TextBox Then
        c.Text = ""
    End If
Next

Replace the (CONTAINER) by the name of yours (it may be a FORM, a PANEL, a GROUPBOX)
Pay attention to which you had included your controls in.

Answer 2

I've done something similar and this is basically how I went about doing it. The only change I might suggest would be instead of overloading the method, just make the passed in type a Control and you can use the same version for GroupBox, Panel, or any other container control that provides a .Controls property. Other than that, I think the definition of "clearing" a control can be somewhat ambiguous and thus there's no Clear() method belonging to the Control class so you need to implement what that means for your purposes for each control type.

Answer 3

Why not just have one routine

ClearAllControls(ByRef container As Control, Optional ByVal Recurse As Boolean = True)

You can recurse into it regardless of what level in the hierarchy you begin the call, from the form level down to a single container.

Also, on the TextBox controls, I use Textbox.Text = String.Empty

Answer 4

This comes straight from an article discussing techniques to use now that Control Arrays have been done away with going from VB6 to VB.NET.

Private Sub ClearForm(ByVal ctrlParent As Control)
    Dim ctrl As Control
    For Each ctrl In ctrlParent.Controls
        If TypeOf ctrl Is TextBox Then
           ctrl.Text = ""
        End If
        ' If the control has children, 
        ' recursively call this function
        If ctrl.HasChildren Then
            ClearForm(ctrl)
        End If
    Next
End Sub