From Nish.

//code starts here

namespace msclr
{
    namespace interop
    {
        template<> ref class context_node<System::Drawing::Font^, HFONT> : public context_node_base
        {
        private:
            System::Drawing::Font^ _font;
	
        public:
            context_node(System::Drawing::Font^% to, HFONT from)
            {
                to = _font = System::Drawing::Font::FromHfont((IntPtr)from);
            }
	
            ~context_node()
            {
                this->!context_node();
            }
	
        protected:
            !context_node()
            {
                delete _font;
            }
        };
	
        template<> ref class context_node<HFONT, System::Drawing::Font^> : public context_node_base
        {
        private:
            HFONT _hFont;
	
        public:
            context_node(HFONT& to, System::Drawing::Font^ from)
            {
                to = _hFont = (HFONT)from->ToHfont().ToPointer();
            }
	
            ~context_node()
            {
                this->!context_node();
            }
	
        protected:
            !context_node()
            {
                DeleteObject(_hFont);
            }
        };
    }
}

//code ends here

Wow. Our first use of a context. Instead of writing a function that implements a specialization of the template function, you write a class that implements a specialization of the template class. Since it's a class, it can have member variables, which you clean up when the context goes out of scope.

Here's how you might use it:

HFONT hFont = CreateSampleFont();
	
//...
	
marshal_context context;
	
System::Drawing::Font^ font =
    context.marshal_as<System::Drawing::Font^>(hFont);
HFONT hFontCopy = context.marshal_as<HFONT>(font);
	
//...
	
DeleteObject(hFont);

Kate