Trapping PowerPoint 2010 events while doing presentation

Is there a way I can trap even开发者_C百科t when a presenter switches to a slide on PowerPoint 2010?

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Figured out myself.

We can do that using VSTO. Below link has some information to get started

http://msdn.microsoft.com/en-us/library/bb960904(office.12).aspx#PPT2007CreatingAddIns_ReactingtoanApplicationLevelEvent