在php中从SAML获取第二个AttributeValue

<saml:Attribute
xmlns:x500="urn:oasis:names:tc:SAML:2.0:profiles:attribute:X500"
x500:Encoding="LDAP"
NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri"
Name="urn:oid:1.3.6.1.4.1.5923.1.1.1.1"
FriendlyName="eduPersonAffiliation">
   <saml:AttributeValue
     xsi:type="xs:string">member</saml:AttributeValue>
   <saml:AttributeValue
     xsi:type="xs:string">staff</saml:AttributeValue>
 </saml:Attribute>

I want to get the second value (staff) out of SAML in my php code, the code looks exaclty like shown above. How can this be reached?

You can use SimpleSAMLphp's API

$as = new SimpleSAML_Auth_Simple('default-sp');
$as->requireAuth();
$attributes = $as->getAttributes();
// The attribute Name is the key
$secondValue = $attributes['urn:oid:1.3.6.1.4.1.5923.1.1.1.1'][1];