How do I Call MainPage.xaml.cpp function from Unity C# script [UWP]

How would I call a function defined in MainPage.xaml.cpp from a script in Unity with il2cpp for UWP?

Such as...

bool TheBool = false;



bool MainPage::GetBool()

{

    return TheBool;

}

I believe I need a cpp file in the plugins folder. I just have no idea what would go in it.

I have in my script:

    [DllImport("__Internal")]

    private static extern bool GetBool();

And in MainPage.xaml.cpp:

bool TheBool = false;



extern "C" __declspec(dllexport)

bool __stdcall MainPage::GetBool()

{

    return TheBool;

}

Any help would be appreciated.