Build data path and projects data path on postprocess build.

How do I distinguish the project's data path and the build data path on postprocess build? I want to copy files from project's assets' folder ("Assets/Files") to build data's folder ("*_Data/ Resources"). How do I do it? When I just do t$$anonymous$$s:

 File.Copy(Application.dataPath + "/Files" + file, Application.persistentDataPath + "/Resources/");

Unity t$$anonymous$$nks I want to copy files from ("Assets/Files") to ("Assets/Resources") but I want to copy the files to built application's data folder. How to do it?