You want to submit a file on FileExchange here in MATLAB, and then you remember your file has a lot of dependencies. You should copy and paste everything on a single folder, zip the folder, delete the useless folder and submit everything.
This function does everything for you. Just type
organizeFileForSubmission('myfile.m'). You'll find the zip file "myfile.zip" with, inside, the main function and the dependency functions in a subfolder, ready for the submission.
If you want you can specify a different name with a second argument,
Create scripts with code, output, and formatted text in a single executable document.