"Can't assign to readonly property'"

Don't you just hate it when VB says this? You want to change the style property of a option button or check box, but it is read only at runtime. What can you do? You could load up a second checkbox . . . or you could use the API. In this neat little tip, you can change the style property at run time:

Declarations

Copy this code into the declarations section of a module:

Declare Function GetWindowLong Lib "user32" _
Alias "GetWindowLongA" 
(ByVal hwnd As Long, ByVal nIndex As Long) As Long

Declare Function SetWindowLong Lib "user32" Alias _
"SetWindowLongA" 
(ByVal hwnd As Long, ByVal nIndex As Long, ByVal _
dwNewLong As Long) As Long

Public Const GWL_STYLE = (-16)
Public Const BS_PUSHLIKE = &H1000&

Procedure

Public Sub SetGraphicStyle(StyleButton As Control, _
Flag As Boolean)
Dim curstyle As Long
Dim newstyle As Long

If Not TypeOf StyleButton Is OptionButton And _
Not TypeOf StyleButton Is CheckBox Then Exit Sub

curstyle = GetWindowLong(StyleButton.hwnd, GWL_STYLE)

If Flag Then
curstyle = curstyle Or BS_PUSHLIKE
Else
curstyle = curstyle And (Not BS_PUSHLIKE)
End If

newstyle = SetWindowLong(StyleButton.hwnd, GWL_STYLE, _
curstyle)

StyleButton.Refresh

End Sub