https://sourceforge.net/tracker/?func=detail&aid=3292558&group_id=152762&atid=785194

As summary , browser support you get the file name after you pick a file from file input,
so we have a chance to validate the file name.

Check the pure client test case.
http://jsfiddle.net/ayXwU/

what you could use is only the file name , the folder path should not be considered,
because the chrome will return you a "c:\fakepath\<real-file-name>" .

It's better to provide a event for this ,
and make developer have a change to stop it if the file name he didn't like it.