upload a file with full path.

I posted this question but did not get the correct answer that I hope. Maybe the question I posted was not clear.
I want to develop a page for uploading a file and then the file (text or csv) can be copy into a database. 
the clients (can be any one who has an account to access the page) can click a button to open a folder in his/her local computer as the file actually is downloaded from the web. Which means any client with access right to the page can open the downloaded file and then copy it into the database in the server. Therefore, my code needs flexiable at this point as diferent client could put the file in any folder in the local computer.
So question is: Is there anyway I can know the fullpath when clicking uploadfile or other control method so that I can use the path for the code?
I could write my code like: string filePath = "C:\\temp\\file.csv"; but in that way the file must be put under that folder, otherwise, it w ...