Download files

[Anon]

I need to make some validation when a file is going to be downloaded, if everything is ok, a "save as .." window must show up, someone knows how could i do this last thing?

[Anon]

this code lets ppl download a pdf file outside web addressable ($DOCUMENT_ROOT) and this page checks for cookies so no unauthorised users download the file by typing dl.php3?filename=some.pdf

php_track_vars;
if(!$HTTP_COOKIE_VARS["cookie_email"]) {
include("loginplease.inc");
} else {
if(@$fp=fopen("file_system_path/$filename","r")) {
Header("Content-Type: application/pdf");
Header("Content-Disposition: attachment; filename=$filename");
readfile("filesystempath/$filename");
fclose($fp);
} else {
echo "sorry file not found";
}

}

the above page is dl.php3.
make a page x.php3 with a link to dl.php3 with $filename as the query string.

[frymaster]

there's a more generic way to do it:

1. replace Content-Type: application/pdf with Content-Type: application/octet-stream

2. Force the name of the downloaded file (ie what it's called on the client's machine, not the server) with
   Content-Disposition: attachment; filename=foo
   Where foo is whatever you wan the downloaded file to be called

3. Force a content length header too
   Content-Length strlen($foobar)
   Where $foobar is the file you sending from the server

4. use:
   Pragma: no-cache
   Cache-control: no-cache, must-revalidate
   to essentially return the browser to the page that called your download script. ie, if you have a page foo.php that has a link "click here to download" and that link leads to bar.php where all the above validating and downloading is done, this cache stuff will force the browser to go back to foo.php after the download is done. Since you've already sent some headers you can't just use header("Location:") so this is a good idea.

-frymaster

[alexeen]

I have been learning PHP for a while now, and recently, i found out that many people asks for downloading PDF files and problems they experience. Well, I've manage to spend some time into this, maybe it will help. I have many operating systems and different types of browsers installed on them.

First of all, i think they've fixed the attachment; bug and so it is REQUIRED to use the word attachment; in the header("Content-Disposition: ...) or else IE will not prompt for download.

Secondly, many people used the header("Content-Length: ...".filesize($filename)); in their script, and this will cause Windows 98(SE)/ Win95 / Win ME with internet explorer 5.x fail to download the PDF file. The result of this will be a 0 byte file since the filesize($filename) did not return any values at all. So if you just leave it out, everything will work fine. (BTW: why specify it anyway??!!??)

Thirdly, I used header("Content-Type: application/RFC822"); and not octet-stream.

Below is the script i used for my web site. Hope this helps.

Note: The script below must be executed by a GET method with parameters $WEBSITE, $PATH, $FILENAME.

=============================================

<?

header ("Pragma: no-cache");
header ("Expires: 0");
header ("Cache-Control: no-cache, no-store, must-revalidate, post-check=0, pre-check=0");

$full_file_path = $WEBSITE.$PATH.$FILENAME;

// --- debug purposes --- echo(filesize($full_file_path));

if (($REQUEST_METHOD != "GET") || !isset($FILENAME) || ($FILENAME == NULL)) {
header("Location: ".$WEBSITE);
exit();
} else {

// --- Do Not Use --- header("Content-Type: application/octet-stream");
header("Content-Type: application/RFC822");
header("Content-Disposition: attachment; filename=\"".$FILENAME."\"");
// --- Do Not Use --- header("Content-Length: ".filesize($full_file_path));

@readfile($full_file_path);

exit();

}

?>

=============================================