..  include:: /Includes.rst.txt
..  index:: Events; BeforePageIsResolvedEvent
..  _BeforePageIsResolvedEvent:

=========================
BeforePageIsResolvedEvent
=========================

..  versionadded:: 12.0
    This PSR-14 event replaces the
    :php:`$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['tslib/class.tslib_fe.php']['determineId-PreProcessing']`
    hook.

The PSR-14 event :php:`\TYPO3\CMS\Frontend\Event\BeforePageIsResolvedEvent` is
processed when the main class :php:`TypoScriptFrontendController` is resolving a
page and its root line, based on the incoming request.

The event fires before the frontend process attempts to fully resolve a given
page based on its page ID and request. Event listeners can modify incoming
parameters (such as :php:`$controller->id`) or the context for resolving a page.

..  note::
    There are three events in the process when the main
    :php:`TypoScriptFrontendController` class resolves a page and its root line
    based on the incoming request. They are triggered in the following order:

    *   BeforePageIsResolvedEvent
    *   :ref:`AfterPageWithRootLineIsResolvedEvent`
    *   :ref:`AfterPageAndLanguageIsResolvedEvent`

Example
=======

..  include:: /_includes/EventsContributeNote.rst.txt

API
===

..  include:: /CodeSnippets/Events/Frontend/BeforePageIsResolvedEvent.rst.txt