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Insert a new slide into a presentation

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This topic shows how to use the classes in the Open XML SDK to insert a new slide into a presentation programmatically.

Getting a PresentationDocument Object

In the Open XML SDK, the PresentationDocument class represents a presentation document package. To work with a presentation document, first create an instance of the PresentationDocument class, and then work with that instance. To create the class instance from the document call the Open method that uses a file path, and a Boolean value as the second parameter to specify whether a document is editable. To open a document for read/write, specify the value true for this parameter as shown in the following using statement. In this code segment, the presentationFile parameter is a string that represents the full path for the file from which you want to open the document.

// Open the source document as read/write. 
using (PresentationDocument presentationDocument = PresentationDocument.Open(presentationFile, true))

With v3.0.0+ the Close() method has been removed in favor of relying on the using statement. This ensures that the Dispose() method is automatically called when the closing brace is reached. The block that follows the using statement establishes a scope for the object that is created or named in the using statement, in this case presentationDocument.

Basic Presentation Document Structure

The basic document structure of a PresentationML document consists of a number of parts, among which is the main part that contains the presentation definition. The following text from the ISO/IEC 29500 specification introduces the overall form of a PresentationML package.

The main part of a PresentationML package starts with a presentation root element. That element contains a presentation, which, in turn, refers to a slide list, a slide master list, a notes master list, and a handout master list. The slide list refers to all of the slides in the presentation; the slide master list refers to the entire slide masters used in the presentation; the notes master contains information about the formatting of notes pages; and the handout master describes how a handout looks.

A handout is a printed set of slides that can be provided to an audience.

As well as text and graphics, each slide can contain comments and notes, can have a layout, and can be part of one or more custom presentations. A comment is an annotation intended for the person maintaining the presentation slide deck. A note is a reminder or piece of text intended for the presenter or the audience.

Other features that a PresentationML document can include the following: animation, audio, video, and transitions between slides.

A PresentationML document is not stored as one large body in a single part. Instead, the elements that implement certain groupings of functionality are stored in separate parts. For example, all authors in a document are stored in one authors part while each slide has its own part.

ISO/IEC 29500: 2016

The following XML code example represents a presentation that contains two slides denoted by the IDs 267 and 256.

    <p:presentation xmlns:p="…" … > 
       <p:sldMasterIdLst>
          <p:sldMasterId
             xmlns:rel="https://…/relationships" rel:id="rId1"/>
       </p:sldMasterIdLst>
       <p:notesMasterIdLst>
          <p:notesMasterId
             xmlns:rel="https://…/relationships" rel:id="rId4"/>
       </p:notesMasterIdLst>
       <p:handoutMasterIdLst>
          <p:handoutMasterId
             xmlns:rel="https://…/relationships" rel:id="rId5"/>
       </p:handoutMasterIdLst>
       <p:sldIdLst>
          <p:sldId id="267"
             xmlns:rel="https://…/relationships" rel:id="rId2"/>
          <p:sldId id="256"
             xmlns:rel="https://…/relationships" rel:id="rId3"/>
       </p:sldIdLst>
           <p:sldSz cx="9144000" cy="6858000"/>
       <p:notesSz cx="6858000" cy="9144000"/>
    </p:presentation>

Using the Open XML SDK, you can create document structure and content using strongly-typed classes that correspond to PresentationML elements. You can find these classes in the namespace. The following table lists the class names of the classes that correspond to the sld, sldLayout, sldMaster, and notesMaster elements.

PresentationML Element Open XML SDK Class Description
<sld/> Slide Presentation Slide. It is the root element of SlidePart.
<sldLayout/> SlideLayout Slide Layout. It is the root element of SlideLayoutPart.
<sldMaster/> SlideMaster Slide Master. It is the root element of SlideMasterPart.
<notesMaster/> NotesMaster Notes Master (or handoutMaster). It is the root element of NotesMasterPart.

How the Sample Code Works

The sample code consists of two overloads of the InsertNewSlide method. The first overloaded method takes three parameters: the full path to the presentation file to which to add a slide, an integer that represents the zero-based slide index position in the presentation where to add the slide, and the string that represents the title of the new slide. It opens the presentation file as read/write, gets a PresentationDocument object, and then passes that object to the second overloaded InsertNewSlide method, which performs the insertion.

// Insert a slide into the specified presentation.
public static void InsertNewSlide(string presentationFile, int position, string slideTitle)
{
    // Open the source document as read/write. 
    using (PresentationDocument presentationDocument = PresentationDocument.Open(presentationFile, true))
    {
        // Pass the source document and the position and title of the slide to be inserted to the next method.
        InsertNewSlide(presentationDocument, position, slideTitle);
    }
}

The second overloaded InsertNewSlide method creates a new Slide object, sets its properties, and then inserts it into the slide order in the presentation. The first section of the method creates the slide and sets its properties.

// Insert the specified slide into the presentation at the specified position.
public static SlidePart InsertNewSlide(PresentationDocument presentationDocument, int position, string slideTitle)
{
    PresentationPart? presentationPart = presentationDocument.PresentationPart;

    // Verify that the presentation is not empty.
    if (presentationPart is null)
    {
        throw new InvalidOperationException("The presentation document is empty.");
    }

    // Declare and instantiate a new slide.
    Slide slide = new Slide(new CommonSlideData(new ShapeTree()));
    uint drawingObjectId = 1;

    // Construct the slide content.            
    // Specify the non-visual properties of the new slide.
    CommonSlideData commonSlideData = slide.CommonSlideData ?? slide.AppendChild(new CommonSlideData());
    ShapeTree shapeTree = commonSlideData.ShapeTree ?? commonSlideData.AppendChild(new ShapeTree());
    NonVisualGroupShapeProperties nonVisualProperties = shapeTree.AppendChild(new NonVisualGroupShapeProperties());
    nonVisualProperties.NonVisualDrawingProperties = new NonVisualDrawingProperties() { Id = 1, Name = "" };
    nonVisualProperties.NonVisualGroupShapeDrawingProperties = new NonVisualGroupShapeDrawingProperties();
    nonVisualProperties.ApplicationNonVisualDrawingProperties = new ApplicationNonVisualDrawingProperties();

    // Specify the group shape properties of the new slide.
    shapeTree.AppendChild(new GroupShapeProperties());

The next section of the second overloaded InsertNewSlide method adds a title shape to the slide and sets its properties, including its text.

// Declare and instantiate the title shape of the new slide.
Shape titleShape = shapeTree.AppendChild(new Shape());

drawingObjectId++;

// Specify the required shape properties for the title shape. 
titleShape.NonVisualShapeProperties = new NonVisualShapeProperties
    (new NonVisualDrawingProperties() { Id = drawingObjectId, Name = "Title" },
    new NonVisualShapeDrawingProperties(new Drawing.ShapeLocks() { NoGrouping = true }),
    new ApplicationNonVisualDrawingProperties(new PlaceholderShape() { Type = PlaceholderValues.Title }));
titleShape.ShapeProperties = new ShapeProperties();

// Specify the text of the title shape.
titleShape.TextBody = new TextBody(new Drawing.BodyProperties(),
        new Drawing.ListStyle(),
        new Drawing.Paragraph(new Drawing.Run(new Drawing.Text() { Text = slideTitle })));

The next section of the second overloaded InsertNewSlide method adds a body shape to the slide and sets its properties, including its text.

// Declare and instantiate the body shape of the new slide.
Shape bodyShape = shapeTree.AppendChild(new Shape());
drawingObjectId++;

// Specify the required shape properties for the body shape.
bodyShape.NonVisualShapeProperties = new NonVisualShapeProperties(new NonVisualDrawingProperties() { Id = drawingObjectId, Name = "Content Placeholder" },
        new NonVisualShapeDrawingProperties(new Drawing.ShapeLocks() { NoGrouping = true }),
        new ApplicationNonVisualDrawingProperties(new PlaceholderShape() { Index = 1 }));
bodyShape.ShapeProperties = new ShapeProperties();

// Specify the text of the body shape.
bodyShape.TextBody = new TextBody(new Drawing.BodyProperties(),
        new Drawing.ListStyle(),
        new Drawing.Paragraph());

The final section of the second overloaded InsertNewSlide method creates a new slide part, finds the specified index position where to insert the slide, and then inserts it and assigns the new slide to the new slide part.

// Create the slide part for the new slide.
SlidePart slidePart = presentationPart.AddNewPart<SlidePart>();

// Assign the new slide to the new slide part
slidePart.Slide = slide;

// Modify the slide ID list in the presentation part.
// The slide ID list should not be null.
SlideIdList? slideIdList = presentationPart.Presentation.SlideIdList;

// Find the highest slide ID in the current list.
uint maxSlideId = 1;
SlideId? prevSlideId = null;

OpenXmlElementList slideIds = slideIdList?.ChildElements ?? default;

foreach (SlideId slideId in slideIds)
{
    if (slideId.Id is not null && slideId.Id > maxSlideId)
    {
        maxSlideId = slideId.Id;
    }

    position--;
    if (position == 0)
    {
        prevSlideId = slideId;
    }

}

maxSlideId++;

// Get the ID of the previous slide.
SlidePart lastSlidePart;

if (prevSlideId is not null && prevSlideId.RelationshipId is not null)
{
    lastSlidePart = (SlidePart)presentationPart.GetPartById(prevSlideId.RelationshipId!);
}
else
{
    string? firstRelId = ((SlideId)slideIds[0]).RelationshipId;
    // If the first slide does not contain a relationship ID, throw an exception.
    if (firstRelId is null)
    {
        throw new ArgumentNullException(nameof(firstRelId));
    }

    lastSlidePart = (SlidePart)presentationPart.GetPartById(firstRelId);
}

// Use the same slide layout as that of the previous slide.
if (lastSlidePart.SlideLayoutPart is not null)
{
    slidePart.AddPart(lastSlidePart.SlideLayoutPart);
}

// Insert the new slide into the slide list after the previous slide.
SlideId newSlideId = slideIdList!.InsertAfter(new SlideId(), prevSlideId);
newSlideId.Id = maxSlideId;
newSlideId.RelationshipId = presentationPart.GetIdOfPart(slidePart);

Sample Code

The following is the complete sample code in both C# and Visual Basic.

// Insert a slide into the specified presentation.
public static void InsertNewSlide(string presentationFile, int position, string slideTitle)
{
    // Open the source document as read/write. 
    using (PresentationDocument presentationDocument = PresentationDocument.Open(presentationFile, true))
    {
        // Pass the source document and the position and title of the slide to be inserted to the next method.
        InsertNewSlide(presentationDocument, position, slideTitle);
    }
}
// Insert the specified slide into the presentation at the specified position.
public static SlidePart InsertNewSlide(PresentationDocument presentationDocument, int position, string slideTitle)
{
    PresentationPart? presentationPart = presentationDocument.PresentationPart;

    // Verify that the presentation is not empty.
    if (presentationPart is null)
    {
        throw new InvalidOperationException("The presentation document is empty.");
    }

    // Declare and instantiate a new slide.
    Slide slide = new Slide(new CommonSlideData(new ShapeTree()));
    uint drawingObjectId = 1;

    // Construct the slide content.            
    // Specify the non-visual properties of the new slide.
    CommonSlideData commonSlideData = slide.CommonSlideData ?? slide.AppendChild(new CommonSlideData());
    ShapeTree shapeTree = commonSlideData.ShapeTree ?? commonSlideData.AppendChild(new ShapeTree());
    NonVisualGroupShapeProperties nonVisualProperties = shapeTree.AppendChild(new NonVisualGroupShapeProperties());
    nonVisualProperties.NonVisualDrawingProperties = new NonVisualDrawingProperties() { Id = 1, Name = "" };
    nonVisualProperties.NonVisualGroupShapeDrawingProperties = new NonVisualGroupShapeDrawingProperties();
    nonVisualProperties.ApplicationNonVisualDrawingProperties = new ApplicationNonVisualDrawingProperties();

    // Specify the group shape properties of the new slide.
    shapeTree.AppendChild(new GroupShapeProperties());
    // Declare and instantiate the title shape of the new slide.
    Shape titleShape = shapeTree.AppendChild(new Shape());

    drawingObjectId++;

    // Specify the required shape properties for the title shape. 
    titleShape.NonVisualShapeProperties = new NonVisualShapeProperties
        (new NonVisualDrawingProperties() { Id = drawingObjectId, Name = "Title" },
        new NonVisualShapeDrawingProperties(new Drawing.ShapeLocks() { NoGrouping = true }),
        new ApplicationNonVisualDrawingProperties(new PlaceholderShape() { Type = PlaceholderValues.Title }));
    titleShape.ShapeProperties = new ShapeProperties();

    // Specify the text of the title shape.
    titleShape.TextBody = new TextBody(new Drawing.BodyProperties(),
            new Drawing.ListStyle(),
            new Drawing.Paragraph(new Drawing.Run(new Drawing.Text() { Text = slideTitle })));
    // Declare and instantiate the body shape of the new slide.
    Shape bodyShape = shapeTree.AppendChild(new Shape());
    drawingObjectId++;

    // Specify the required shape properties for the body shape.
    bodyShape.NonVisualShapeProperties = new NonVisualShapeProperties(new NonVisualDrawingProperties() { Id = drawingObjectId, Name = "Content Placeholder" },
            new NonVisualShapeDrawingProperties(new Drawing.ShapeLocks() { NoGrouping = true }),
            new ApplicationNonVisualDrawingProperties(new PlaceholderShape() { Index = 1 }));
    bodyShape.ShapeProperties = new ShapeProperties();

    // Specify the text of the body shape.
    bodyShape.TextBody = new TextBody(new Drawing.BodyProperties(),
            new Drawing.ListStyle(),
            new Drawing.Paragraph());
    // Create the slide part for the new slide.
    SlidePart slidePart = presentationPart.AddNewPart<SlidePart>();
    
    // Assign the new slide to the new slide part
    slidePart.Slide = slide;

    // Modify the slide ID list in the presentation part.
    // The slide ID list should not be null.
    SlideIdList? slideIdList = presentationPart.Presentation.SlideIdList;

    // Find the highest slide ID in the current list.
    uint maxSlideId = 1;
    SlideId? prevSlideId = null;

    OpenXmlElementList slideIds = slideIdList?.ChildElements ?? default;

    foreach (SlideId slideId in slideIds)
    {
        if (slideId.Id is not null && slideId.Id > maxSlideId)
        {
            maxSlideId = slideId.Id;
        }

        position--;
        if (position == 0)
        {
            prevSlideId = slideId;
        }

    }

    maxSlideId++;

    // Get the ID of the previous slide.
    SlidePart lastSlidePart;

    if (prevSlideId is not null && prevSlideId.RelationshipId is not null)
    {
        lastSlidePart = (SlidePart)presentationPart.GetPartById(prevSlideId.RelationshipId!);
    }
    else
    {
        string? firstRelId = ((SlideId)slideIds[0]).RelationshipId;
        // If the first slide does not contain a relationship ID, throw an exception.
        if (firstRelId is null)
        {
            throw new ArgumentNullException(nameof(firstRelId));
        }

        lastSlidePart = (SlidePart)presentationPart.GetPartById(firstRelId);
    }

    // Use the same slide layout as that of the previous slide.
    if (lastSlidePart.SlideLayoutPart is not null)
    {
        slidePart.AddPart(lastSlidePart.SlideLayoutPart);
    }

    // Insert the new slide into the slide list after the previous slide.
    SlideId newSlideId = slideIdList!.InsertAfter(new SlideId(), prevSlideId);
    newSlideId.Id = maxSlideId;
    newSlideId.RelationshipId = presentationPart.GetIdOfPart(slidePart);

    return slidePart;
}

See also