soap xml 响应 - 如何获取顽固的数据

Question

我正在尝试获取faultstring元素的内容，而且我更习惯于 SimpleXML 的对象语法 ( $xml->...->faultstring.) 下面的 DomDocument 方法有效，但我更愿意坚持使用 SimpleXML。

PHP 版本 5.6.40，Libxml 2.9.1。

$xmlResponse = '<?xml version="1.0" encoding="utf-8"?>

    <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">

        <soap:Body>

            <soap:Fault>

                <faultcode>soap:Client</faultcode>

                <faultstring>Server did not recognize the value of HTTP Header SOAPAction: https://gw1.domain.com:4430/.</faultstring>

                <detail />

            </soap:Fault>

        </soap:Body>

    </soap:Envelope>';

// DOES NOT WORK

$xml = simplexml_load_string($xmlResponse,NULL,NULL,"http://schemas.xmlsoap.org/soap/envelope/");

$faultstring = (string) ($xml->Body->Fault->faultstring);

var_dump($faultstring);

// WORKS

$_DomObject = new DOMDocument;

$_DomObject->loadXML($xmlResponse);

if (!$_DomObject) die("Error while parsing the document");

$s = simplexml_import_dom($_DomObject);

foreach(['faultcode','faultstring','detail'] as $tag) {

    echo $tag.' => '.$_DomObject->getElementsByTagName($tag)[0]->textContent.'<br/>';

}