php soap 调用.net web service

$userapi = 'http://localhost/Wcf/Service.svc?singleWsdl';

$soap = new SoapClient($userapi);

$params = array('appKey'=>$key, 'appSecret'=>$secret); //GetApp 方法的参数
$a= $soap->GetApp($params); //执行服务的 GetApp方法