public static function createUniqueFilename($prefix, $extension = '', $randomChars = 32, $onlyReturnRandomizedPart = false, $charList = null)
{
do {
$random = StringTools::random($randomChars, $charList);
$file = $prefix . $random . $extension;
$exists = file_exists($file);
} while ($exists);
if ($onlyReturnRandomizedPart) {
return $random;
}
return $file;
}