user_guide_src/source/installation/upgrade_responses.rst
Upgrade Output Class ####################
.. contents:: :local: :depth: 2
Output Class Documentation CodeIgniter 3.x <http://codeigniter.com/userguide3/libraries/output.html>_HTTP Responses Documentation CodeIgniter 4.x </outgoing/response>set_content_type() from version 3 is now named setContentType() and so on.$this->output to $this->response followed by the method. You can find all methods in :doc:../outgoing/response... literalinclude:: upgrade_responses/ci3sample/001.php
.. literalinclude:: upgrade_responses/001.php