php调用wcf,webservice

function sendsms() {
$rtn = "";
$wcfURL = 'http://xxxxxx/SendMessageService.svc?wsdl';
$wcfClient = new SoapClient($wcfURL);
$args = array(
'phoneNumber' => '',
'smsContent' => "",
'signature' => '',
'username' => '',
'password' => ''
);
$rtn = $wcfClient->__soapCall($args);
$rtn = $wcfClient->SendMessage ( $args );

dump($rtn);

}