Merging PowerPoint slides using OpenXML

Question

All I want to do is merge some slides into a master presentation using OpenXML SDK, I don't want to use Introp as it's not ideal in a server environment, I've tried many code samples but the merged presentation always shows me repair message, when I compared the corrupted file with the repaired one I found out that the ids aren't generated correctly.

Is there any open source library or sample code that actually works. I've heard of Aspose but it's a paid library.

Answer 1

The Microsoft MSDN article

http://msdn.microsoft.com/en-us/library/office/ee361883(v=office.12).aspx

gives a step by step instruction on how to merge powerpoint presentations together.

It takes care of ensuring the ID's are unique. The only disadvantage is that it also copies the slide masters for each and every slide, making the final powerpoint file larger than expected.

Answer 2

Try presentation builder code, at http://openxmldeveloper.org/.

Answer 3

Yes u face issues if id's are not unique, below is working code i am using. I know its old thread, but in case if some one is looking for answer,

public static void MergeSlides(string presentationFolder, string sourcePresentation, string destPresentation)
{
    int id = 0;

    // Open the destination presentation.
    using (PresentationDocument myDestDeck = PresentationDocument.Open(presentationFolder + destPresentation, true))
    {
        PresentationPart destPresPart = myDestDeck.PresentationPart;

        // If the merged presentation does not have a SlideIdList element yet, add it.
        if (destPresPart.Presentation.SlideIdList == null)
            destPresPart.Presentation.SlideIdList = new SlideIdList();

        // Open the source presentation. This will throw an exception if the source presentation does not exist.
        using (PresentationDocument mySourceDeck = PresentationDocument.Open(presentationFolder + sourcePresentation, false))
        {
            PresentationPart sourcePresPart = mySourceDeck.PresentationPart;

            // Get unique ids for the slide master and slide lists for use later.
            uniqueId = GetMaxSlideMasterId(destPresPart.Presentation.SlideMasterIdList);

            uint maxSlideId = GetMaxSlideId(destPresPart.Presentation.SlideIdList);

            // Copy each slide in the source presentation, in order, to the destination presentation.
            foreach (SlideId slideId in sourcePresPart.Presentation.SlideIdList)
            {
                SlidePart sp;
                SlidePart destSp;
                SlideMasterPart destMasterPart;
                string relId;
                SlideMasterId newSlideMasterId;
                SlideId newSlideId;

                // Create a unique relationship id.
                id++;
                sp = (SlidePart)sourcePresPart.GetPartById(slideId.RelationshipId);

                relId = sourcePresentation.Remove(sourcePresentation.IndexOf('.')) + id;

                // Add the slide part to the destination presentation.
                destSp = destPresPart.AddPart<SlidePart>(sp, relId);

                // The slide master part was added. Make sure the relationship between the main presentation part and
                // the slide master part is in place.
                destMasterPart = destSp.SlideLayoutPart.SlideMasterPart;
                destPresPart.AddPart(destMasterPart);

                // Add the slide master id to the slide master id list.
                uniqueId++;
                newSlideMasterId = new SlideMasterId();
                newSlideMasterId.RelationshipId = destPresPart.GetIdOfPart(destMasterPart);
                newSlideMasterId.Id = uniqueId;

                destPresPart.Presentation.SlideMasterIdList.Append(newSlideMasterId);

                // Add the slide id to the slide id list.
                maxSlideId++;
                newSlideId = new SlideId();
                newSlideId.RelationshipId = relId;
                newSlideId.Id = maxSlideId;

                destPresPart.Presentation.SlideIdList.Append(newSlideId);
            }

            // Make sure that all slide layout ids are unique.
            FixSlideLayoutIds(destPresPart);
        }

        // Save the changes to the destination deck.
        destPresPart.Presentation.Save();
    }
}

   public static void FixSlideLayoutIds(PresentationPart presPart)
    {
        //Need to make sure all slide layouts have unique ids
        foreach (SlideMasterPart slideMasterPart in presPart.SlideMasterParts)
        {
            foreach (SlideLayoutId slideLayoutId in slideMasterPart.SlideMaster.SlideLayoutIdList)
            {
                uniqueId++;
                slideLayoutId.Id = (uint)uniqueId;
            }
            slideMasterPart.SlideMaster.Save();
        }
    }