Loading and unloading WPF assembly from arbitrary path

Question

I'm currently struggling to find a way to load and unload a WPF assembly from an arbitrary path (not a sub directory of the base path) from a C# console application.

I'm exploring stackoverflow for a couple of days (as I have done with some other forums), but I can't actually find a way how to get the console application loading the WPF assembly and instantiating an object from the assembly.

Starting point is following example as C# console application:

using WPFLibrary;

namespace Caller
{
    class Program
    {
        [STAThread]
        static void Main(string[] args)
        {
            SampleWindow wnd = new SampleWindow();
            wnd.ShowDialog();
        }
     }
 }

and the following code as WPF assembly:

namespace WPFLibrary
{   
    public partial class SampleWindow : Window
    {       
        public SampleWindow()
        {
            InitializeComponent();
        }
   }
}

I found various similar questions and suggestions to use:

• Reflection via: Assembly.Load();
• Using Activator.CreateInstance();
• Using a different AppDomain with CreateInstanceAndUnwrap
• Using AssemblyResolve for the AppDomain etc.
• etc

But I could never get my simple example above working if the WPFLibrary is not in a sub directory of the base path of the Caller console application. Since I'm new in this field I may just have missed a simple thing or this scenario may be completely impossible.... Any help would be appreciated.

Background of this question:

In case you are not interested to understand my motivation for this question just skip the remaining of this post. We are developing an c++ dll application for a commercial CAD system. The interface for this system is c/c++ only so there no way to change the complete code to a C# application. This application includes a simple scripting language which also allows to define and execute a graphical user interface. Currently this is encoded in a win32 / MFC way, but since it includes a self build layout manager it is obviously a good idea to think about other alternatives. A perfect match seems to be use use WPF, but that requires to use .NET and to allow XAML definitions a C# library connected by a C++/CLI dll seems to be a good setup.

Some major requirements are:

• The WPF dll must be able to be load from the installation of the application.
• It is required to stop and restart the application (so also the WPF assembly needs to be removed and reloaded).

Answer 1

I had to do something kind of similar, although from my console app I was starting up a WPF app. Maybe this will help:

    static void Main(string[] args)
    {
        Initialise();
        if (!RunSilently)
            FireUpGui();
        else
            RunConsoleApp();   // not so relevant to the answer
    }
    private static void FireUpGui()
    {
        Console.SetWindowSize(80, 5);
        Thread t = new Thread(Start_Wpf);
        t.SetApartmentState(ApartmentState.STA);
        t.Start();
    }
    static App WpfApp;
    static void Start_Wpf()
    {
        WpfApp = new App();   // my WPF App
        WpfApp.Run();
    }

It's worth noting though that my App class was in the same assembly as my console app, which meant I already referenced the normal WPF framework assemblies.