# Merge Presentations

> Merge complete decks or selected slides and choose between source design and a destination layout.

Source: https://docs.aspose.com/slides/net/examples/presentations/merge/
Updated: 2026-10-31



Merge complete decks or selected slides and choose between source design and a destination layout.

## Download and run

Download [the complete project](example.zip) and open **Example.sln** in a compatible IDE. Automatic NuGet restore should run when it opens. The project accepts supported installed release SDKs instead of requiring one exact patch. [Setup and supported environments](/slides/net/examples/getting-started/) explains native libraries, fonts and the SDK/runtime distinction.

```text
dotnet run --project Example.csproj -- --mode evaluation
```

Evaluation mode needs no license and retains the SDK watermark/text limits. For full licensed checks, set ASPOSE_LICENSE_PATH to your authorized license and use --mode licensed. Fonts and synthetic fixtures needed by this recipe are included or acquired as documented. The supplied bootstrap prepares a separate output workspace and prints its absolute path. The complete download includes that bootstrap, solution and editor profiles; the C# block below is Program.cs from the same archive.


## Input and prerequisites

The code creates its own synthetic input. Use a compatible stable SDK with the included Aspose.Slides.NET6.CrossPlatform 26.10.0 project; .NET 10 LTS is recommended. Evaluation mode performs the recipe without a license and retains the SDK watermark and text limits. Licensed mode additionally checks unrestricted content using your authorized license.

[Download the complete project](example.zip), including the solution, source, configuration and bundled fonts. No license is distributed.

## Example

The program creates two three-slide presentations with distinct master backgrounds, notes and sections. AddClone(sourceSlide) retains the source design in this fixture. Its layout overload places the green source slide on a blue destination layout. Removing the destination's default slide avoids an unexpected blank first slide.

```csharp
using System.Threading.Tasks;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text.Json;
using Aspose.Slides;
using Aspose.Slides.Export;

internal static class Program
{
    private static ExampleContext Context = null!;
    private static Task<int> Main(string[] args) => ExampleBootstrap.RunAsync(args, async context =>
    {
        Context = context;
        context.BeginAction("presentations/merge/block-001");
        RunExample();
        await Task.CompletedTask;
        context.Pass("presentations/merge/block-001", "recipe semantic assertions", "source inputs preserved", "documented output generated");
    });

    private static void CreateDeck(string path, string prefix, Color color)
    {
        using var deck = new Presentation();
        deck.SlideSize.SetSize(640, 360, SlideSizeScaleType.DoNotScale);
        deck.Masters[0].Background.Type = BackgroundType.OwnBackground;
        deck.Masters[0].Background.FillFormat.FillType = FillType.Solid;
        deck.Masters[0].Background.FillFormat.SolidFillColor.Color = color;
        var blank = deck.LayoutSlides.GetByType(SlideLayoutType.Blank);
        for (int i = 0; i < 3; i++)
        {
            ISlide slide = i == 0 ? deck.Slides[0] : deck.Slides.AddEmptySlide(blank);
            Label(slide, prefix + (i + 1));
            slide.NotesSlideManager.AddNotesSlide().NotesTextFrame.Text = "Notes for " + prefix + (i + 1);
        }
        deck.Sections.AddSection("Opening", deck.Slides[0]);
        deck.Sections.AddSection("Details", deck.Slides[1]);
        deck.Save(path, SaveFormat.Pptx);
    }

    private static void CheckOrder(string path, params string[] expected)
    {
        using var result = new Presentation(path);
        Require(result.Slides.Count == expected.Length, "Extra or missing slide in " + path);
        Require(result.Slides.Select(Text).SequenceEqual(expected), "Wrong slide order in " + path);
    }

    private static void RunExample()
    {
        CreateDeck("blue.pptx", "A", Color.LightBlue);
        CreateDeck("green.pptx", "B", Color.LightGreen);
        string blueHash = Hash("blue.pptx"), greenHash = Hash("green.pptx");
        using var blue = new Presentation("blue.pptx");
        using var green = new Presentation("green.pptx");
        using (var merged = new Presentation())
        {
            merged.Slides.RemoveAt(0); // Remove the destination's default blank slide.
            foreach (var slide in blue.Slides) merged.Slides.AddClone(slide);
            foreach (var slide in green.Slides) merged.Slides.AddClone(slide);
            merged.Save("merged.pptx", SaveFormat.Pptx);
        }
        CheckOrder("merged.pptx", "A1", "A2", "A3", "B1", "B2", "B3");
        using (var merged = new Presentation("merged.pptx"))
        {
            Require(merged.Slides[0].LayoutSlide.MasterSlide.Background.FillFormat.SolidFillColor.Color.ToArgb() == Color.LightBlue.ToArgb(), "Blue master was lost.");
            Require(merged.Slides[3].LayoutSlide.MasterSlide.Background.FillFormat.SolidFillColor.Color.ToArgb() == Color.LightGreen.ToArgb(), "Green master was lost.");
            Require(merged.Slides[3].NotesSlideManager.NotesSlide.NotesTextFrame.Text.Contains(Context.ExpectedText("Notes for B1")), "Speaker notes were lost.");
            using var first = merged.Slides[0].GetImage(new Size(640, 360));
            first.Save("source-design-blue.png", Aspose.Slides.ImageFormat.Png);
            using var fourth = merged.Slides[3].GetImage(new Size(640, 360));
            fourth.Save("source-design-green.png", Aspose.Slides.ImageFormat.Png);
        }
        using (var selected = new Presentation())
        {
            selected.Slides.RemoveAt(0);
            selected.Slides.AddClone(blue.Slides[2]);
            selected.Slides.AddClone(green.Slides[0]);
            selected.Save("selected.pptx", SaveFormat.Pptx);
        }
        CheckOrder("selected.pptx", "A3", "B1");
        using (var destination = new Presentation("blue.pptx"))
        {
            destination.Slides.RemoveAt(0);
            destination.Slides.RemoveAt(0);
            destination.Slides.RemoveAt(0);
            var destinationLayout = destination.LayoutSlides.GetByType(SlideLayoutType.Blank);
            destination.Slides.AddClone(green.Slides[0], destinationLayout);
            destination.Save("destination-design.pptx", SaveFormat.Pptx);
        }
        CheckOrder("destination-design.pptx", "B1");
        using (var result = new Presentation("destination-design.pptx"))
        {
            Require(result.Slides[0].LayoutSlide.MasterSlide.Background.FillFormat.SolidFillColor.Color.ToArgb() == Color.LightBlue.ToArgb(), "Destination layout was not applied.");
            using var image = result.Slides[0].GetImage(new Size(640, 360));
            image.Save("destination-design.png", Aspose.Slides.ImageFormat.Png);
        }
        Require(Hash("blue.pptx") == blueHash && Hash("green.pptx") == greenHash, "A source file changed.");
        Report(new { merged_slides = 6, selected_slides = 2, order_verified = true, source_masters_retained = true, destination_layout_applied = true, notes_retained = true, originals_unchanged = true });
    }


    private static void Require(bool condition, string message)
    {
        if (!condition) throw new InvalidOperationException(message);
    }

    private static IAutoShape Label(ISlide slide, string text)
    {
        var shape = slide.Shapes.AddAutoShape(ShapeType.Rectangle, 50, 80, 540, 100);
        shape.Name = "content-" + text;
        shape.TextFrame.Text = text;
        shape.TextFrame.Paragraphs[0].Portions[0].PortionFormat.FontHeight = 28;
        return shape;
    }

    private static string Text(ISlide slide) => string.Join("|", slide.Shapes.OfType<IAutoShape>().Where(s => s.Name.StartsWith("content-", StringComparison.Ordinal)).Select(s => s.TextFrame.Text));
    private static string Hash(string file) => Convert.ToHexString(SHA256.HashData(File.ReadAllBytes(file)));
    private static void Report(object checks)
    {
        string json = JsonSerializer.Serialize(new { checks }, new JsonSerializerOptions { WriteIndented = true });
        File.WriteAllText("result.json", json);
        Console.WriteLine(json);
    }
}
```

## Run and check the result

Extract the project into an empty working directory, restore its locked packages, then run it:

```text
dotnet restore Example.csproj --locked-mode
dotnet run --project Example.csproj --configuration Release --no-restore
```

The example writes "blue.pptx", "green.pptx", "merged.pptx", "selected.pptx", "destination-design.pptx", "source-design-blue.png", "source-design-green.png", "destination-design.png" and "result.json". It reopens the generated presentation files and checks the expected data. A failed check raises an exception; successful checks are recorded in "result.json".


## Output previews

![source design blue](source-design-blue.png)

![source design green](source-design-green.png)

![destination design](destination-design.png)


## Practical limits

The output order follows the application loop. Importing slides does not automatically recreate the source decks' named section organization; create destination sections deliberately if you need them. Applying a layout changes master/layout-based design, not explicit formatting on individual shapes. These checks cover the demonstrated content and do not promise preservation of every feature or format.

See the [detailed guide](/slides/net/merge-presentation/) and [individual slide examples](/slides/net/examples/elements/slide/).