在ThisAddIn_Startup函數中調用 Globals.ThisAddIn.Application.SlideSelectionChanged += new Microsoft.Office.Interop.PowerPoint.EApplication_SlideSelectionChangedEventHandler(Application_SlideSelectionChanged); 即可，如下：

   private void ThisAddIn_Startup(object sender, System.EventArgs e)
        {      
                   
            //幻燈片切換時調用的事件       
           Globals.ThisAddIn.Application.SlideSelectionChanged += new Microsoft.Office.Interop.PowerPoint.EApplication_SlideSelectionChangedEventHandler(Application_SlideSelectionChanged);
        }

    
       
        //幻燈片切換時執行的函數
        void Application_SlideSelectionChanged(PowerPoint.SlideRange sldRange)
        {
            #region 自己的相關邏輯       
            #endregion
        }

vsto之PPT幻燈片切換事件