This property is used by read
modules that support frames or sub-documents.
Frames are numbered from one upwards. The default of zero
indicates that a default frame or frame set should be used.
The SwfVector module uses this property when the Operation is null. When this occurs a temporary
is created and the
ProcessingObjectEventArgs.Info.FrameNumber is set to the value
of this property. The default behavior is to read frame one.
The MSOffice module uses this property to allow you to read
individual worksheets from within an Excel spreadsheet. The default
behavior is to read all the worksheets in order rather than simply
select one of them.