add function parameter doc, add regexp to remove chars which could break the file download/name header
add function parameter doc, add regexp to remove chars which could break the file download/name header

thexerteproject/xerteonlinetoolkits,thexerteproject/xerteonlinetoolkits,torinfo/xerteonlinetoolkits,thexerteproject/xerteonlinetoolkits,torinfo/xerteonlinetoolkits,thexerteproject/xerteonlinetoolkits,torinfo/xerteonlinetoolkits,torinfo/xerteonlinetoolkits,thexerteproject/xerteonlinetoolkits,torinfo/xerteonlinetoolkits