PHP - 是否可以根据referrer / previous page url创建文件夹？

I'm trying to write a code which would create folder based on referer - url which was form submitted from. Something like this:

if( !is_dir($_SERVER['HTTP_REFERER'] . '/gallery/') ) {
    mkdir($_SERVER['HTTP_REFERER'] . '/gallery/', 0750, true );
}

Is it possible?

The problem is, that the HTTP_REFERER is a full URL and not a file path. So you have to convert it to a path and strip some problematic characters. Something like this should do the trick:

// convert HTTP_REFERER from a URL to a path
$referer = str_replace('http://'.$_SERVER['HTTP_HOST'].'/', '', $_SERVER['HTTP_REFERER']);
// replace all unwanted characters with underscores
$referer_folder = preg_replace('/[^\w\/]+/', '_', $referer);
// set the absolute dir path
$dir = __DIR__ . '/' . $referer_folder . '/gallery/';

if( !is_dir($dir) ) {
    mkdir($dir, 0750, true );
}