Enumerating PowerPoint slides in order

Question

I'm trying to analyze an existing PowerPoint 2010 .pptx file using the OpenXML SDK 2.0.

What I'm trying to achieve is to

enumerate the slides in order (as they appear in the PPTX)
extracting all textual bits from each slide

I've started and gotten so far - I can enumerate the SlideParts from the PresentationPart - but I cannot seem to find a way to make this an ordered enumeration - the slides are being returned in pretty much arbitrary order...

Any trick to get these slides in the order defined in the PPTX file?

using (PresentationDocument doc = PresentationDocument.Open(fileName, false))
{
   // Get the presentation part of the document.
   PresentationPart presentationPart = doc.PresentationPart;

   foreach (var slide in presentationPart.SlideParts)
   {
        ...
   }
}

I was hoping to find something like a SlideID or Sequence number or something - some item or property I could use in a Linq expression like

.OrderBy(s => s.SlideID)

on that slideparts collection.

I believe the SlideID property does not relate to the position of the slide in the file - it is set when the slide is created, and as the slide is moved around, it doesn't change. In VBA, there is a separate property "SlideIndex" (order of slides) and "SlideNumber" (number on the slide). I think `SlideIndex` would be what you need... — Floris, Feb 19 '13 at 17:39
@Floris: cannot find neither `SlideNumber` nor `SlideIndex` in the OpenXML object model ... — marc_s, Feb 19 '13 at 17:41

score 7 · Accepted Answer · answered Feb 20 '13 at 18:07

It's a bit more involved than I had hoped for - and the docs are a bit sketchy at times....

Basically, I had to enumerate the SlideIdList on the PresentationPart and do some XML-foo to get from that SlideId to the actual slide in the OpenXML presentation.

Something along the lines of:

using (PresentationDocument doc = PresentationDocument.Open(fileName, false))
{
    // Get the presentation part of the document.
    PresentationPart presentationPart = doc.PresentationPart;

    // get the SlideIdList
    var items = presentationPart.Presentation.SlideIdList;

    // enumerate over that list
    foreach (SlideId item in items)
    {
        // get the "Part" by its "RelationshipId"
        var part = presentationPart.GetPartById(item.RelationshipId);

        // this part is really a "SlidePart" and from there, we can get at the actual "Slide"
        var slide = (part as SlidePart).Slide;

        // do more stuff with your slides here!
    }
}

Presentation presentation = presentationPart.Presentation; // Verify that the slide ID list exists. if (presentation.SlideIdList != null) { IEnumerable slidePartList = presentationPart.SlideParts; foreach (SlidePart slidePart in slidePartList) { //YourCode } we can use in this way also. — madan, Sep 18 '15 at 11:50

score 2 · Answer 2 · answered Feb 19 '13 at 22:29

The closest I found was this snippet:

[ISO/IEC 29500-1 1st Edition]

sld (Presentation Slide)

This element specifies a slide within a slide list. The slide list is used to specify an ordering of slides.

[Example: Consider the following custom show with an ordering of slides.

<p:custShowLst>
  <p:custShow name="Custom Show 1" id="0">
    <p:sldLst>
      <p:sld r:id="rId4"/>
      <p:sld r:id="rId3"/>
      <p:sld r:id="rId2"/>
      <p:sld r:id="rId5"/>
    </p:sldLst>
  </p:custShow>
</p:custShowLst>In the above example the order specified to present the slides is slide 4, then 3, 2 and finally 5. end example]

In the MSDN documentation for the slide class

It seems that slides have an r:id of the form rId## where ## is the number of the slide. Maybe that's enough to get you going again?

Enumerating PowerPoint slides in order

2 Answers2