添加设置删除Http Headers内容

$headers = Yii::$app->response->headers;
// add a Pragma header. Existing Pragma headers will NOT be overwritten.
$headers->add('Pragma', 'no-cache');
// set a Pragma header. Any existing Pragma headers will be discarded.
$headers->set('Pragma', 'no-cache');
// remove Pragma header(s) and return the removed Pragma header values in an array
$values = $headers->remove('Pragma');