How can I read the number of layers in an .ai file?

[WangZiXiao-ChenDu]

Magick.NET version

13.5.0

Environment (Operating system, version and so on)

C#

Description

How can I read the number of layers in an .ai file?
001.zip

Steps to Reproduce

using ImageMagick;

using (MagickImageCollection images = new MagickImageCollection())
{
images.Read(inputFilePath);
}

[dlemstra]

You can use PdfInfo.Create(inputFilePath) to get the number of layers in the .ai file?

[WangZiXiao-ChenDu]

PdfInfo.Create

This way, the layer information cannot be obtained.
The .ai file in the example has four layers.

[dlemstra]

When I use ImageMagick on the command line this file also contains a single layer. You might want to reach out to GhostScript who's program we use to read this file and ask why we only get one layer? Maybe the other layers are invisible?