How can I set the HTTP status code?

Question

I'm trying to set a 404 HTTP status response code for an ajax controller action in a plugin.

Yii has a response object where the code can be set, but I can't find a way to access it from craft.

Answer 1

I believe HeaderHelper::setHeader() is what you're looking for in the context of a plugin.

Answer 2

In Craft3, the correct way of setting HTTP status codes is

Craft::$app->getResponse()->setStatusCode(404);

Answer 3

HeaderHelper::setHeader(array('status' => 404));

Answer 4

http_response_code(404);
return $this->returnErrorJson('Something happened, try again.');