I can not get file name and save to database

I'll be more specific, I have the system that works as follows, it scans a folder and takes all the txt files from the folder and shows me in the form of a link, clicking on the link it shows me what's inside txt files. I have a form that should register in the database the name of the file txt and a note about the same, there that is catching, I can not get the name of the file and write in the database the your name and an observation about it.

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