Convert PPT and PPTX to PDF in C# [Advanced Features Included]

Overview

Converting PowerPoint presentations (PPT, PPTX, ODP) into PDF format in C# offers several advantages, including ensuring compatibility across different devices and preserving the layout and formatting of your presentation. This guide demonstrates how to convert presentations to PDF documents, utilize various options to control image quality, include hidden slides, password protect PDF documents, detect font substitutions, select specific slides for conversion, and apply compliance standards to output documents.

PowerPoint to PDF Conversions

Using Aspose.Slides, you can convert presentations in these formats to PDF:

  • PPT
  • PPTX
  • ODP

To convert a presentation to PDF, you simply have to pass the file name as an argument in the Presentation class and then save the presentation as a PDF using a Save method. The Presentation class exposes the Save method that is typically used to convert a presentation to PDF.

Aspose.Slides allows you to convert:

  • Entire presentations to PDF
  • Specific slides in a presentation to PDF

Aspose.Slides exports presentations to PDF, ensuring the contents of the resulting PDFs closely match the original presentations. Elements and attributes are rendered accurately in the conversion, including:

  • Images
  • Text boxes and shapes
  • Text formatting
  • Paragraph formatting
  • Hyperlinks
  • Headers and footers
  • Bullets
  • Tables

Convert PowerPoint to PDF

The standard PowerPoint PDF conversion operation is executed using default options. In this case, Aspose.Slides tries to convert the provided presentation to PDF using optimal settings at the maximum quality levels.

This C# code shows you how to convert a PowerPoint (PPT, PPTX, ODP) to PDF:

// Instantiates a Presentation class that represents a PowerPoint file, it could be PPT, PPTX, ODP etc.
Presentation presentation = new Presentation("PowerPoint.ppt");

// Saves the presentation as a PDF
presentation.Save("PDF-result.pdf", SaveFormat.Pdf);

Convert PowerPoint to PDF with Options

Aspose.Slides provides custom options—properties under the PdfOptions class—that allow you to customize the PDF (resulting from the conversion process), lock the PDF with a password, or even specify how the conversion process should go.

Convert PowerPoint to PDF with Custom Options

Using custom conversion options, you can set your preferred quality setting for raster images, specify how metafiles should be handled, set a compression level for texts, set DPI for images, etc.

The code example below demonstrates an operation in which a PowerPoint presentation is converted to PDF with several custom options:

// Instantiates the PdfOptions class
PdfOptions pdfOptions = new PdfOptions
{
    // Sets the quality for JPG images
    JpegQuality = 90,

    // Sets DPI for images
    SufficientResolution = 300,

    // Sets the behavior for metafiles
    SaveMetafilesAsPng = true,

    // Sets the text compression level for textual content
    TextCompression = PdfTextCompression.Flate,

    // Defines the PDF compliance mode
    Compliance = PdfCompliance.Pdf15
};

// Instantiates the Presentation class that represents a PowerPoint document
using (Presentation presentation = new Presentation("PowerPoint.pptx"))
{
    // Saves the presentation as a PDF document
    presentation.Save("PowerPoint-to-PDF.pdf", SaveFormat.Pdf, pdfOptions);
}

Convert PowerPoint to PDF with Hidden Slides

If a presentation contains hidden slides, you can use a custom option—the ShowHiddenSlides property from the PdfOptions class—to instruct Aspose.Slides to include the hidden slides as pages in the resulting PDF.

This C# code shows you how to convert a PowerPoint presentation to PDF with hidden slides included:

// Instantiates a Presentation class that represents a PowerPoint file
Presentation presentation = new Presentation("PowerPoint.pptx");

// Instantiates the PdfOptions class
PdfOptions pdfOptions = new PdfOptions();

// Adds hidden slides
pdfOptions.ShowHiddenSlides = true;

// Saves the presentation as a PDF
presentation.Save("PowerPoint-to-PDF.pdf", SaveFormat.Pdf, pdfOptions);

Convert PowerPoint to Password Protected PDF

This C# code shows you how to convert a PowerPoint to a password-protected PDF (using protection parameters from the PdfOptions class):

// Instantiates a Presentation object that represents a PowerPoint file
Presentation presentation = new Presentation("PowerPoint.pptx");

/// Instantiates the PdfOptions class
PdfOptions pdfOptions = new PdfOptions();

// Sets PDF password and access permissions
pdfOptions.Password = "password";
pdfOptions.AccessPermissions = PdfAccessPermissions.PrintDocument | PdfAccessPermissions.HighQualityPrint;

// Saves the presentation as a PDF
presentation.Save("PPTX-to-PDF.pdf", SaveFormat.Pdf, pdfOptions);

Detect Font Substitutions

Aspose.Slides provides the WarningCallback property under the SaveOptions class to allow you to detect font substitutions in a presentation to PDF conversion process.

This C# code shows you how to detect font substitutions: xxx

public static void Main()
{
    LoadOptions loadOptions = new LoadOptions();
    FontSubstSendsWarningCallback warningCallback = new FontSubstSendsWarningCallback();
    loadOptions.WarningCallback = warningCallback;

    using (Presentation pres = new Presentation("pres.pptx", loadOptions))
    {
    }
}

private class FontSubstSendsWarningCallback : IWarningCallback
{
    public ReturnAction Warning(IWarningInfo warning)
    {
        if (warning.WarningType == WarningType.CompatibilityIssue)
            return ReturnAction.Continue;

        if (warning.WarningType == WarningType.DataLoss &&
            warning.Description.StartsWith("Font will be substituted"))
        {
            Console.WriteLine($"Font substitution warning: {warning.Description}");
        }

        return ReturnAction.Continue;
    }
}

Convert Selected Slides in PowerPoint to PDF

This C# code shows you how to convert specific slides in a PowerPoint presentation to PDF:

// Instantiates a Presentation object that represents a PowerPoint file
Presentation presentation = new Presentation("PowerPoint.pptx");

// Sets an array of slides positions
int[] slides = { 1, 3 };

// Saves the presentation as a PDF
presentation.Save("PPTX-to-PDF.pdf", slides, SaveFormat.Pdf);

Convert PowerPoint to PDF with Custom Slide Size

This C# code shows you how to convert a PowerPoint when its slide size is specified to a PDF:

// Load the PowerPoint presentation
using (Presentation presentation = new Presentation("SelectedSlides.pptx"))
{
    // Create a new presentation for adjusted slide size
    using (Presentation resizedPresentation = new Presentation())
    {
        // Clone the first slide from the original presentation
        ISlide slide = presentation.Slides[0];
        resizedPresentation.Slides.InsertClone(0, slide);

        // Set custom slide size (e.g., 612x792 points)
        resizedPresentation.SlideSize.SetSize(612F, 792F, SlideSizeScaleType.EnsureFit);

        // Configure PDF options to include notes at the bottom
        PdfOptions pdfOptions = new PdfOptions
        {
            SlidesLayoutOptions = new NotesCommentsLayoutingOptions
            {
                NotesPosition = NotesPositions.BottomFull
            }
        };

        // Save the resized presentation to a PDF with notes
        resizedPresentation.Save("PDFnotes_out.pdf", SaveFormat.Pdf, pdfOptions);
    }
}

Convert PowerPoint to PDF in Notes Slide View

This C# code shows you how to convert a PowerPoint to PDF notes:

// Load the PowerPoint presentation
using (Presentation presentation = new Presentation("NotesFile.pptx"))
{
    // Configure PDF options with Notes Layout
    PdfOptions pdfOptions = new PdfOptions
    {
        SlidesLayoutOptions = new NotesCommentsLayoutingOptions
        {
            NotesPosition = NotesPositions.BottomFull
        }
    };

    // Save the presentation to a PDF with notes
    presentation.Save("Pdf_Notes_out.pdf", SaveFormat.Pdf, pdfOptions);
}

Accessibility and Compliance Standards for PDF

Aspose.Slides allows you to use a conversion procedure that complies with Web Content Accessibility Guidelines (WCAG). You can export a PowerPoint document to PDF using any of these compliance standards: PDF/A1a, PDF/A1b, and PDF/UA.

This C# code demonstrates a PowerPoint to PDF conversion operation in which multiple PDFs based on different compliance standards are obtained:

using (Presentation pres = new Presentation("pres.pptx"))
{
    pres.Save("pres-a1a-compliance.pdf", SaveFormat.Pdf, new PdfOptions()
    {
        Compliance = PdfCompliance.PdfA1a
    });
   
    pres.Save("pres-a1b-compliance.pdf", SaveFormat.Pdf, new PdfOptions()
    {
        Compliance = PdfCompliance.PdfA1b
    });
   
    pres.Save("pres-ua-compliance.pdf", SaveFormat.Pdf, new PdfOptions()
   {
        Compliance = PdfCompliance.PdfUa
    });
}

Frequently Asked Questions

1. Can I convert multiple PowerPoint files to PDF in bulk?

Yes, Aspose.Slides supports batch conversion of multiple PPT/PPTX files to PDF. You can iterate through your files and apply the conversion process programmatically.

2. Is it possible to password-protect the converted PDF?

Absolutely. Use the PdfOptions class to set a password and define access permissions during the conversion process.

3. How do I include hidden slides in the PDF?

Set the ShowHiddenSlides property in the PdfOptions class to true to include hidden slides in the resulting PDF.

4. Can Aspose.Slides maintain high image quality in the PDF?

Yes, you can control image quality by setting properties like JpegQuality and SufficientResolution in the PdfOptions class to ensure high-quality images in your PDF.

5. Does Aspose.Slides support PDF/A compliance standards?

Yes, Aspose.Slides allows you to export PDFs that comply with various standards, including PDF/A1a, PDF/A1b, and PDF/UA, ensuring your documents meet accessibility and archival requirements.

Additional Resources

Convert PowerPoint to PNG in C# Convert PowerPoint to PDF with Notes in C#