Examine Presentation

Aspose.Slides for .NET allows you to examine a presentation to find out its properties and understand its behavior.

Info

The PresentationInfo and DocumentProperties classes contain the properties and methods used in operations here.

Check a Presentation Format

Before working on a presentation, you may want to find out what format (PPT, PPTX, ODP, and others) the presentation is in at the moment.

You can check a presentation’s format without loading the presentation. See this C# code:

IPresentationInfo info = PresentationFactory.Instance.GetPresentationInfo("pres.pptx");
Console.WriteLine(info.LoadFormat); // PPTX

IPresentationInfo info2 = PresentationFactory.Instance.GetPresentationInfo("pres.ppt");
Console.WriteLine(info2.LoadFormat); // PPT

IPresentationInfo info3 = PresentationFactory.Instance.GetPresentationInfo("pres.odp");
Console.WriteLine(info3.LoadFormat); // ODP

Get Presentation Properties

This C# code shows you how to get presentation properties (information about the presentation):

IPresentationInfo info = PresentationFactory.Instance.GetPresentationInfo("pres.pptx");
IDocumentProperties props = info.ReadDocumentProperties();
Console.WriteLine(props.CreatedTime);
Console.WriteLine(props.Subject);
Console.WriteLine(props.Title);
// .. 

You may want to see the properties under the DocumentProperties class.

Update Presentation Properties

Aspose.Slides provides the PresentationInfo.UpdateDocumentProperties method that allows you to make changes to presentation properties.

Let’s say we have a PowerPoint presentation with the document properties shown below.

This code example shows you how to edit some presentation properties:

string fileName = "sample.pptx";

IPresentationInfo info = PresentationFactory.Instance.GetPresentationInfo(fileName);

IDocumentProperties properties = info.ReadDocumentProperties();
properties.Title = "My title";
properties.LastSavedTime = DateTime.Now;

info.UpdateDocumentProperties(properties);
info.WriteBindedPresentation(fileName);

The results of changing the document properties are shown below.

Useful Links

To get more information about a presentation and its security attributes, you may find these links useful:

• Checking whether a Presentation is Encrypted
• Checking whether a Presentation is Write Protected (read-only)
• Checking whether a Presentation is Password Protected Before Loading it
• Confirming the Password Used to Protect a Presentation.

FAQ

How can I check whether fonts are embedded and which ones they are?

Look for embedded-font information at the presentation level, then compare those entries with the set of fonts actually used across content to identify which fonts are critical for rendering.

How can I quickly tell if the file has hidden slides and how many?

Iterate through the slide collection and inspect each slide’s visibility flag.

Can I detect whether custom slide size and orientation are used, and whether they differ from the defaults?

Yes. Compare the current slide size and orientation with the standard presets; this helps anticipate behavior for printing and export.

Is there a quick way to see if charts reference external data sources?

Yes. Traverse all charts, check their data source, and note whether the data is internal or link-based, including any broken links.

How can I assess ‘heavy’ slides that may slow rendering or PDF export?

For each slide, tally object counts and look for large images, transparency, shadows, animations, and multimedia; assign a rough complexity score to flag potential performance hotspots.