My dll and "ExDll.h"

I want to write a dll.
If add the header file "ExDll.h" into my dll.I can refer to my dll in NSIS script like the following way?

mydll::myfunciton .....

Must I include "ExDll.h" ?
🙄
Thanks.

It would be very nice to have good "How-to" about creating DLL's. I know, that it isn't topic related with NSIS.

Start with Exaples\Plugin which creates a plug-in that exports myFunction and work your way from there. Change the function's name, add more functions, add some stack magic and add your code.