如何在php中将curl xml响应转换为数组？

$url = "https://example.com/api/xml";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/xml'));
$response = curl_exec($ch);
curl_close($ch);

$xml = simplexml_load_string($response);
$array = json_decode(json_encode($xml), true);