3.6 Programmable Tags Example


This file format allows for the storage of programmable tags at three levels—on the document itself, on each slide, and on each shape. While the primary purpose of programmable tags is to provide a mechanism for a third-party VBA add-in to persist opaque data in the file, they are also used as a way for a later version of PowerPoint to store new records in the file that will be safely ignored and preserved by an earlier version. The following sections show an example of this extension mechanism on the document and slide-levels.