Create Presentations in .NET

Create PowerPoint Presentation

To add a simple plain line to a selected slide of the presentation, please follow the steps below:

1. Create an instance of Presentation class.
2. Obtain the reference of a slide by using its Index.
3. Add an AutoShape of Line type using AddAutoShape method exposed by Shapes object.
4. Write the modified presentation as a PPTX file.

In the example given below, we have added a line to the first slide of the presentation.

// Instantiate a Presentation object that represents a presentation file
using (Presentation presentation = new Presentation())
{
    // Get the first slide
    ISlide slide = presentation.Slides[0];

    // Add an autoshape of type line
    slide.Shapes.AddAutoShape(ShapeType.Line, 50, 150, 300, 0);
    presentation.Save("NewPresentation_out.pptx", SaveFormat.Pptx);
}

Create and Save Presentation

Steps: Create and Save Presentation in C#

1. Create an instance of Presentation class.
2. Save Presentation to any format supported by SaveFormat

Presentation presentation = new Presentation();

presentation.Save("OutputPresenation.pptx", SaveFormat.Pptx);

Open and Save Presentation

Steps: Open and Save Presentation in C#

1. Create an instance of Presentation class with any format i.e. PPT, PPTX, ODP etc.
2. Save Presentation to any format supported by SaveFormat

// Load any supported file in Presentation e.g. ppt, pptx, odp etc.
Presentation presentation = new Presentation("Sample.odp");

presentation.Save("OutputPresenation.pptx", SaveFormat.Pptx);

FAQ

What formats can I save a new presentation to?

You can save to PPTX, PPT, and ODP, and export to PDF, XPS, HTML, SVG, and images, among others.

Can I start from a template (POTX/POTM) and save as a regular PPTX?

Yes. Load the template and save to the desired format; POTX/POTM/PPTM and similar formats are supported.

How do I control slide size/aspect ratio when creating a presentation?

Set the slide size (including presets like 4:3 and 16:9 or custom dimensions) and choose how content should scale.

In what units are sizes and coordinates measured?

In points: 1 inch equals 72 units.

How do I handle very large presentations (with many media files) to reduce memory usage?

Use BLOB management strategies, limit in-memory storage by leveraging temporary files, and prefer file-based workflows over purely in-memory streams.

Can I create/save presentations in parallel?

You cannot operate on the same Presentation instance from multiple threads. Run separate, isolated instances per thread or process.

How do I remove the trial watermark and limitations?

Apply a license once per process. The license XML must remain unmodified, and the license setup should be synchronized if multiple threads are involved.

Can I digitally sign the PPTX I create?

Yes. Digital signatures (adding and verifying) are supported for presentations.

Are macros (VBA) supported in created presentations?

Yes. You can create/edit VBA projects and save macro-enabled files such as PPTM/PPSM.