t extension
    .lpstrDefExt = DefaultExt
    ' DlgTitle can take dialog box title
    .lpstrTitle = DlgTitle
    
    If (Hook) Then
        ''HookedDialog = Me
        '.lpfnHook = lHookAddress(AddressOf DialogHookFunction)
        '.flags = .flags Or OFN_ENABLEHOOK Or OFN_EXPLORER
        ''Set m_oEventSink = EventSink
    End If
    
    ' Make new filter with bars (|) replacing nulls and double null at end
    Dim ch As String, i As Integer
    For i = 1 To Len(Filter)
        ch = Mid$(Filter, i, 1)
 