yii2: how to response image and let browser show it?

Question

the same work can be done by follow code：

header(\'Content-Type:image/jpeg\');
readfile(\'a.jpg\');

but now I really confused by Yii2\'s

Answer 1

Finally, I did it by follow codes:

$response = Yii::$app->getResponse();
$response->headers->set('Content-Type', 'image/jpeg');
$response->format = Response::FORMAT_RAW;
if ( !is_resource($response->stream = fopen($imgFullPath, 'r')) ) {
   throw new \yii\web\ServerErrorHttpException('file access failed: permission deny');
}
return $response->send();