Prior to Visual Studio 2008 SP1, you couldn’t use common VSTO features like controls in the document and databinding to list objects at the add-in level. But with SP1 we introduced a way for you to use these features at the add-in level. In this section some of the wierd ways Idid things in section 4 will start to make more sense—I designed the code in Section 4 to be easily portable to an add-in. One thing that won’t port to the add-in level is cached data—that feature only works when code is at the document level. Choose File > Add > New Project.
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7. VSTO Bug Tracker : Using Document-Level Features in Add-Ins