Returns a unique ID number for the specified slide. Read-only Long.
Remarks
Unlike the SlideIndex property, the SlideID property of a Slide object won't change when you add slides to the presentation or rearrange the slides in the presentation. Therefore, using the FindBySlideID method with the slide's ID number can be a more reliable way to return a specific Slide object from a Slides collection than using the Item method with the slide's index number.
Example
This example demonstrates how to retrieve the unique ID number for a Slide object and then use this number to return that Slide object from the Slides collection.
Set gslides = ActivePresentation.Slides
'Get slide ID
graphSlideID = gslides.Add(2, ppLayoutChart).SlideID
gslides.FindBySlideID(graphSlideID) _
.SlideShowTransition.EntryEffect = _
ppEffectCoverLeft 'Use ID to return specific slide