主题：窗口中如何引用一类控件

For Each c As WinForm.DropDownBox In e.Form.Children
    c.Enabled = False
Next

For Each c As WinForm.Control In e.Form.Children

   If Typeof c Is WinForm.DropDownBox then

       c.Enabled = False

   End If
Next

如果用e.Form.Controls，碰到复合控件的时候，会把控件中的控件也遍历出来。