动态选择文件的PHP文件大小

I have a php script that needs to determine the size of a file on the file system after being manipulated by a separate php script.

For example, there exists a zip file that has a fixed size but gets an additional file of unknown size inserted into it based on the user that tries to access it. So the page that's serving the file is something like getfile.php?userid=1234.

So far, I know this:

filesize('getfile.php'); //returns the actual file size of the php file, not the result of script execution

readfile('getfile.php'); //same as filesize()

filesize('getfile.php?userid=1234'); //returns false, as it can't find the file matching the name with GET vars attached

readfile('getfile.php?userid=1234'); //same as filesize()

Is there a way to read the result size of the php script instead of just the php file itself?

Someone had posted an option for using curl to do this but removed their answer after a downvote. Too bad, because it's the one way I've gotten this to work. So here's their answer that worked for me:

$ch = curl_init('http://localhost/getfile.php?userid=1234');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); //This was not part of the poster's answer, but I needed to add it to prevent the file being read from outputting with the requesting script
curl_exec($ch);

$size = 0;

if(!curl_errno($ch))
{
    $info = curl_getinfo($ch);
    $size = $info['size_download'];
}

curl_close($ch);

echo $size;

filesize

As of PHP 5.0.0, this function can also be used with some URL wrappers.

something like

filesize('http://localhost/getfile.php?userid=1234');

should be enough

The only way to get the size of the output is to run it and then look. Depending on the script the result might differ though for practical use the best thing to do is to estimate basd on your knowledge. i.e. if you have a 5MB file and add another 5k user specific content it's still about 5MB in the end etc.

To expand on Ivan's answer:

Your string is 'getfile.php' with or without GET parameters, this is being treated as a local file, and therefore retrieving the filesize of the php file itself.

It is being treated as a local file because it isn't starting with the http protocol. See http://us1.php.net/manual/en/wrappers.php for supported protocols.

When using filesize() I got a warning: Warning: filesize() [function.filesize]: stat failed for ...link... in ..file... on line 233

Instead of filesize() I found two working options to replace it:

1) $headers = get_headers($pdfULR, 1); $fileSize = $headers['Content-Length']; echo $fileSize;

2) echo strlen(file_get_contents($pdfULR));

Now it's working fine.