Get Filename from HTTP header Content-Disposition

getFilename.php

<?php

function getFilename($header) {
    if (preg_match('/Content-Disposition:.*?filename="(.+?)"/', $header, $matches)) {
        return $matches[1];
    }
    if (preg_match('/Content-Disposition:.*?filename=([^; ]+)/', $header, $matches)) {
        return rawurldecode($matches[1]);
    }
    throw new Exception(__FUNCTION__ .": Filename not found");
}

$s1 = 'Content-Disposition: attachment; filename="FILE NAME HERE"';
echo getFilename($s1) . PHP_EOL;

$s2 = 'Content-Disposition: attachment; filename=file.ext';
echo getFilename($s2) . PHP_EOL;

$s3 = 'Content-Disposition: attachment; name=file.ext';
echo getFilename($s3) . PHP_EOL;

getFilename2.php

<?php

function getFilename($header) {
    if (preg_match('/filename="(.+?)"/', $header, $matches)) {
        return $matches[1];
    }
    if (preg_match('/filename=([^; ]+)/', $header, $matches)) {
        return rawurldecode($matches[1]);
    }
    throw new Exception(__FUNCTION__ .": Filename not found");
}

header("Content-Type: text/plain;charset=UTF-8");

$s1 = 'attachment; filename="FILE NAME HERE"';
echo getFilename($s1) . PHP_EOL;

$s2 = 'attachment; filename=file.ext';
echo getFilename($s2) . PHP_EOL;

$s3 = $_SERVER['HTTP_CONTENT_DISPOSITION'] ?? "";
echo getFilename($s3) . PHP_EOL;

parseProperties.php

<?php

function parseProperties($message) {
    $properties = explode(';', $message);
    $result = array();
    foreach ($properties as $prop) {
        $property = trim($prop);
        $pos = strpos($property, '=');
        if ($pos > 0)  {
            $key = trim(substr($property, 0, $pos));
            $val = trim(substr($property, $pos+1));
            if (strlen($val) > 0 && $val{0} == '"') {
                $val = substr($val, 1, -1);
            }
            $result[$key] = $val;
        }
    }
    return $result;
}