Learn-WinUI-3-Second-Edition/Chapter10/TemplateStudioSampleApp/Helpers/RuntimeHelper.cs

using System.Runtime.InteropServices;
using System.Text;

namespace TemplateStudioSampleApp.Helpers;

public class RuntimeHelper
{
    [DllImport("kernel32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    private static extern int GetCurrentPackageFullName(ref int packageFullNameLength, StringBuilder? packageFullName);

    public static bool IsMSIX
    {
        get
        {
            var length = 0;

            return GetCurrentPackageFullName(ref length, null) != 15700L;
        }
    }
}