Filepath from same folder as the PBIX file(PowerQuery M language)

Hey PBI'ers,

I have a parameter with a filepath.

with """&FilePath&"" I intergate this as my source in de advanced script editor. 

But it's on my C: hardrive and I want have to implement 130 dashboards with the same data model.

So how can I get the currentfolder where the PBIX file is in + [filename](as my parameter input) in the

M language?

Thanks already, kind regards,

MrNelsch