将文件名中的非字母数字字符转换为下划线

Posted 2021-02-23

Translate non alphanumeric characters into an underscore. Doesn't create double underscores if there's two spaces in a row. Also turns name to lowercase. Use with trim to avoid spaces at front or end.

$filename=trim($_FILES['pdf']['name']);
$name = preg_replace('/[^a-z0-9.]+/', '_', strtolower($filename));