how do i check for existing files so as to not overwrite?

jasonmills58

Hi, I have an admin who is uploading lots of files for lots of different clients. All of the uploaded files are in the same folder, but when my admin uploads files, he only sees the files for the current client. For instance, lets say Sally Jones has a file called superReport.pdf. Well, if we updated Jim Johnson and wanted to upload superReport.pdf to him as well, it would overwrite the report Sally had. So I need to check to see if $filename exists, and then ask the client if they want to overwrite. Maybe I could even mention whose file it is? All the file names are indexed in the database...

thanks!

laserlight

you can try [man]file_exists/man

jasonmills58

thank you. sorry, i should have mentioned that i know about file_exists(). my problem is more about implementation. for instance, where do i make the check? during file upload? how do i ask if they want to overwrite or not?

leatherback

Hi,

you can only check when the file has been submitted (Thus uploaded).
You could then show a page, which asks the user wether the file needs to be overwritten, or to specify a name. You can then have the tempname in a hidden input, and move the file after the user submits again. (I think...)

jasonmills58

hmm, its a good idea, but the tmp file gets deleted as soon as the script is finished. i don't know whether stopping to ask the user a question counts as finished in this case

leatherback

hm.. i think it would.

I personally tack the unix timestamp to the new filename, which makes it a unique name no matter what.
You could (if you do not wat that) move the file with a temp. upload name to the destination dir, ask the user what to if (If there is a file with the desired name already) and then rename (move..) the file.

jasonmills58

i like the timestamp option, actually. is there a way to take it back off? like prepending it with a $timestamp."-".$filename

or something like that?

thanks for your help!

leatherback

This is how i use it (the name is an extra identifier, so I can even check wether the right person is requesting files.):

$time = time();
$finalfile = $_SESSION[displayname]."_".$time."_".$_FILES[file][name];
$oldfiles = explode("_", $finalfile);
$oldfile = oldfiles[2];

jasonmills58

fantastic, thanks leatherback. you're the best