不能识别xmlns:soap,xmlns:xsi,xmlns:xsd。

可以把xmlns:soap改为xmlns-soap再处理。

soap的命名空间不被识别，参考下面代码：

<?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>
        <client_insetResponse xmlns="http://127.0.0.1/webservices/">
            <client_insetResult>0|</client_insetResult>
        </client_insetResponse>
    </soap:Body>
</soap:Envelope>
xml;
    
$xmlObj = simplexml_load_string($xmlStr);
$xmlObj->registerXPathNamespace('soap', 'http://schemas.xmlsoap.org/soap/envelope/');
$result = $xmlObj->xpath("soap:Body");

print_r($result);