如何在symfony中导出为CSV文件中的数据

　　public function executeRegistrantsToCsv(){

　　$id = $this->getRequestParameter('id');

　　$c = new Criteria();

　　$c->add(RegistrantPeer::EVENT_ID, $id);

　　$c->add(RegistrantPeer::STATUS, 1);

　　$this->aObjReg = RegistrantPeer::doSelect($c);

　　$this->forward404Unless($this->aObjReg);

　　$this->setlayout('csv');

　　$this->getResponse()->clearHttpHeaders();

　　$this->getResponse()->setHttpHeader('Content-Type', 'application/vnd.ms-excel');

　　$this->getResponse()->setHttpHeader('Content-Disposition', 'attachment; filename=registrants_report_event_' . $id . '.csv');

　　}

　　Title,Name,Email,Phone,Organisation,State,City,Country,Login Date,IpAddress

　　<? foreach($aObjReg as $r): ?>

　　<?= $r->getTitle() ?>,<?= $r->getName() ?>,<?= $r->getEmail() ?>,<?= $r->getPhone() ?>,<?= $r->getOrganisation() ?>,<?= $r->getState() ?>,<?= $r->getCity() ?>,<?= $r->getCountry() ?>,<?= $r->getLoginDate() ?>,<?= $r->getIpAddress() ?>,

　　<? endforeach ?>