Aspose.Slides for .NET 25.8 Release Notes

New Features and Improvements

Updates to Supported Target Platforms

As part of our ongoing efforts to enhance the quality and security of our product, we are planning to discontinue support for outdated versions of the .NET Framework, such as .NET Framework 2.0, 3.5, and 4.0. These will be replaced with assemblies targeting more modern and secure versions of the .NET platform.

These changes are scheduled to take effect starting with version 25.10.
We recommend updating your projects in advance to ensure compatibility with the supported .NET versions.

For more details about the updates to supported target platforms, please refer to this article.

Public API Changes

Added New Property: CaptionTracks

The new property, CaptionTracks, has been added to the IAudioFrame interface and implemented in the AudioFrame class. This property returns a collection containing all caption tracks.

The following sample code shows how to insert a new AudioFrame, add captions to it, and save the PowerPoint presentation:

using (Presentation pres = new Presentation())
{
    IAudio audio = pres.Audios.AddAudio(File.ReadAllBytes("audio.mp3"));
    var audioFrame = pres.Slides[0].Shapes.AddAudioFrameEmbedded(10, 10, 50, 50, audio);

    // Adds the new captions track from file
    audioFrame.CaptionTracks.Add("New track", "track.vtt");

    pres.Save("audio with captions.pptx", SaveFormat.Pptx);
}

The following example demonstrates how to extract captions from the AudioFrame on the first slide and save them to files:

using (Presentation pres = new Presentation("audio with captions.pptx"))
{
     foreach (IShape shape in pres.Slides[0].Shapes)
     {
         if (shape is IAudioFrame audioFrame)
         {
             foreach (var captionTrack in audioFrame.CaptionTracks)
             {
                 // Saves the caption track's binary data as a .vtt file
                 File.WriteAllBytes(captionTrack.CaptionId + ".vtt", captionTrack.BinaryData);
             }
         }
     }
}

The following example shows how to remove all captions from an AudioFrame and save the PowerPoint presentation:

using (Presentation pres = new Presentation("audio with captions.pptx"))
{
    var audioFrame = pres.Slides[0].Shapes[0] as IAudioFrame;

    // Removes all captions from the AudioFrame
    audioFrame.CaptionTracks.Clear();

    pres.Save("audio without captions.pptx", SaveFormat.Pptx);
}

Added New Methods: IFonts.GetScriptFontMap, IFonts.GetScriptFont, IFonts.SetScriptFont and IFonts.RemoveScriptFont

New methods GetScriptFontMap, GetScriptFont, SetScriptFont and RemoveScriptFont added to IFonts interface and its implementation. These enhancements allow developers to programmatically access, set, remove, and list font mappings for different script tags (e.g., Latn, Cyrl, Jpan) following the BCP-47 script code standard. These APIs are particularly useful for customizing font behavior in multilingual presentations. For example, when working with East Asian, Arabic, Hebrew, or Devanagari scripts, it’s now possible to apply precise font control to match branding or localization requirements.

Code example:

using (Presentation pres = new Presentation(pptxFileName))
{
    IDictionary<string, string> scriptFontMap = pres.MasterTheme.FontScheme.Major.GetScriptFontMap();
    foreach (var kvp in scriptFontMap)
    {
        Console.WriteLine(kvp.Key + " ? " + kvp.Value);
    }

    Console.WriteLine(pres.MasterTheme.FontScheme.Major.GetScriptFont("Thaa"));

    pres.MasterTheme.FontScheme.Major.SetScriptFont("Thaa", "Super Thaa");
    pres.MasterTheme.FontScheme.Minor.RemoveScriptFont("Geor");
}

Added New Methods: SlideUtil.FindShapesByPlaceholderType and SlideUtil.GetTextBoxesContainsText

In previous versions of Aspose.Slides for .NET, there were cases, when adding placeholders from a layout to a slide, the placeholder text was copied along with its shape. Since this behavior does not match that of PowerPoint, starting from Aspose.Slides for .NET 25.8, this inconsistency has been corrected. The new GetTextBoxesContainsText and FindShapesByPlaceholderType methods have been added to the Aspose.Slides.Util.SlideUtil class to make it easier to switch to the new version.

Usage examples:

If you previously used the SlideUtil.GetAllTextBoxes(IBaseSlide slide) method to search for specific text in all slide shapes, including placeholders, for example like this:

using (var presentation = new Presentation())
{
    ISlide slide = presentation.Slides.AddEmptySlide(presentation.LayoutSlides[0]);
    foreach (ITextFrame textFrame in SlideUtil.GetAllTextBoxes(slide))
    {
        if (textFrame.Text.Contains("test text"))
            textFrame.Text = "The new test text!";
    }
}

then you can now use the SlideUtil.GetTextBoxesContainsText(IBaseSlide slide, string text, bool checkPlaceholderText) method with checkPlaceholderText = true to achieve the same functionality:

using (var presentation = new Presentation())
{
    ISlide slide = presentation.Slides.AddEmptySlide(presentation.LayoutSlides[0]);
    foreach (ITextFrame textFrame in SlideUtil.GetTextBoxesContainsText(slide, "test text", true))
    {
        textFrame.Text = "The new test text!";
    }
}

The following example demonstrates how to find all “Text” placeholders on a slide:

using (var presentation = new Presentation(filePath))
{
    foreach (IShape shape in SlideUtil.FindShapesByPlaceholderType(presentation.Slides[0], PlaceholderType.Body))
    {
        switch (shape.Placeholder.Orientation)
        {
            case Orientation.Vertical:
                (shape as IAutoShape).TextFrame.Text = "This is a Text (Vertical) placeholder.";
                continue;
            case Orientation.Horizontal:
                (shape as IAutoShape).TextFrame.Text = "This is a Text placeholder.";
                continue;
        }
    }
}

Implemented Brightness and Contrast Effect reading

Added IBrightnessContrast interface and its implementation BrightnessContrast class

The Aspose.Slides.Effects.BrightnessContrast represents BrightnessContrast effect, which allows you to adjust brightness and contrast.

Added IBrightnessContrastEffectiveData interface and its implementation BrightnessContrastEffectiveData class

The Aspose.Slides.Effects.BrightnessContrastEffectiveData is an immutable object which represents a BrightnessContrast effect.

Added AddBrightnessContrastEffect(float brightness, float contrast) method to the IImageTransformOperationCollection interface and to its implementation ImageTransformOperationCollection class

This method adds the new BrightnessContrast effect to the end of a collection. The brightness is the percent to change the brightness, the contrast is the percent to change the contrast. The method returns the index of the new image effect in a collection.

The following sample code shows how to use new interfaces and classes. Please note that the current implementation doesn’t allow to change brightness and contrast values, the effect is not implemented and cannot be applied. It allows to get brightness and contrast values of BrightnessContrast effect if they are present.

using (var presentation = new Presentation(pathToPresentation))
{
    ISlide slide = presentation.Slides[0];
    IPictureFrame pictureFrame = (IPictureFrame)(slide.Shapes[0]);
    IImageTransformOperationCollection imageTransform = pictureFrame.PictureFormat.Picture.ImageTransform;
    foreach (var effect in imageTransform)
    {
        if (effect is IBrightnessContrast)
        {
            IBrightnessContrast brightnessContrast = (IBrightnessContrast)effect;
            IBrightnessContrastEffectiveData brightnessContrastData = brightnessContrast.GetEffective();
            float brightness = brightnessContrastData.Brightness;
            float contrast = brightnessContrastData.Contrast;
            //...
        }
    }
}

Implemented the ability to extract data from Excel tables and use it in PowerPoint presentations

The following interfaces and classes have been added:

• IExcelDataWorkbook, ExcelDataWorkbook
• IExcelDataCell, ExcelDataCell

Unlike the ChartDataWorkbook, which is designed specifically to handle data used in charts and is tightly integrated with chart-related functionality, the newly introduced types - ExcelDataWorkbook and related classes - offer a more flexible and general-purpose approach to accessing data from Excel workbooks. These types provide read-only access to Excel content, enabling developers to retrieve values from cells, access worksheet names, and interact with Excel structures.

Added IExcelDataWorkbook interface and ExcelDataWorkbook class

The Aspose.Slides.Excel.ExcelDataWorkbook class provides functionality to load an Excel workbook from a file path or stream. It offers several overloads for retrieving data cells.

Added IExcelDataCell interface and ExcelDataCell class

The Aspose.Slides.Excel.ExcelDataCell class represents a single cell in an Excel workbook. It exposes properties such as cell name, position, and value.

The following example demonstrates how to extract a value from a cell:

IExcelDataWorkbook wb = new ExcelDataWorkbook("TestWorkbook.xlsx");
IExcelDataCell cell = wb.GetCell("Sheet1", "B2");
Console.WriteLine(cell.Value);

The following example demonstrates how to retrieve worksheet names and chart names from an Excel workbook:

ExcelDataWorkbook workbook = new ExcelDataWorkbook("excelfile.xlsx");
var sheetNames = workbook.GetWorksheetNames();
foreach (var name in sheetNames)
{
    Console.WriteLine("Worksheet " + name + " has the following charts:");

    var sheetCharts = workbook.GetChartsFromWorksheet(name);
    foreach (var chart in sheetCharts)
        Console.WriteLine(chart.Key + " - " + chart.Value);
}

Support for importing charts from an Excel workbook into a presentation

The new ExcelWorkbookImporter class has been added. It provides functionality for importing content from an Excel workbook into a presentation.

The following example demonstrates how to import all charts from an Excel workbook to a presentation. Only the chart data will be embedded:

ExcelDataWorkbook workbook = new ExcelDataWorkbook("excelfile.xlsx");
using (var pres = new Presentation())
{
    var blankLayout = pres.LayoutSlides.GetByType(SlideLayoutType.Blank);

    var worksheetNames = workbook.GetWorksheetNames();
    foreach (var name in worksheetNames)
    {
        var worksheetCharts = workbook.GetChartsFromWorksheet(name);
        foreach (var chart in worksheetCharts)
        {
            ISlide slide = pres.Slides.AddEmptySlide(blankLayout);
            ExcelWorkbookImporter.AddChartFromWorkbook(slide.Shapes, 10, 10, workbook, name, chart.Key, false);
        }
    }

    pres.Save("result.pptx", SaveFormat.Pptx);
}

The following example demonstrates how to import the chart from a workbook file by its name and worksheet name. The chart will link to the external workbook:

using (var pres = new Presentation())
{
    ExcelWorkbookImporter.AddChartFromWorkbook(pres.Slides[0].Shapes, 10, 10, "excelfile.xlsx", "worksheet name", "chart name", false);
    pres.Save("result.pptx", SaveFormat.Pptx);
}

The following code demonstrates how to import the chart from a workbook stream by its name and worksheet name. The entire workbook will be embedded in the chart:

using (FileStream fStream = new FileStream("excelfile.xlsx", FileMode.Open, FileAccess.Read))
using (var pres = new Presentation())
{
    ExcelWorkbookImporter.AddChartFromWorkbook(pres.Slides[0].Shapes, 10, 10, fStream, "worksheet name", "chart name", true);
    pres.Save("result.pptx", SaveFormat.Pptx);
}