问无法捕获SoapFault异常。坏网关

EN

try {

    $oClient = new SoapClient( $this->CI->config->item('indexing_wsdl_url'),
                                array(
                                    "trace"         => true,
                                    "exceptions"    => true,
                                )
                            );

    $result = $oClient->add(
            array(
                // Application specific parameters goes here
            )
    );// (this is line number 161 as seen in the warning)

} catch (SoapFault $fault) {

    log_message('error', $fault->getMessage());
}