The Hook is a feature in CodeIgniter that provides a way to change the inner working of the framework without hacking the core files. It facilitates you to execute a script with a particular path within the CodeIgniter. Usually, it is defined in the application/config/hooks.php file.
In CodeIgniter, hooks provide a way to tap into and modify the inner workings of the framework without hacking the core files. Hooks allow you to execute a script with a specific name at certain points during the execution of the CodeIgniter application.
Hooks are defined in the application/config/hooks.php file. Each hook is an associative array with two main keys: class and function. The class key specifies the name of the class where the function to be called resides, and the function key specifies the name of the function to be called.
Hooks can be registered at different execution points within the CodeIgniter application’s lifecycle, such as:
pre_system: Before the framework is initialized.pre_controller: Before the controller is called.post_controller_constructor: After the controller is instantiated but before the method is called.post_controller: After the controller is executed.display_override: Used to display the final rendered page.cache_override: Used to perform actions just before the CodeIgniter cache library is initialized.post_system: After the final rendered page is sent to the browser.
When a hook point is reached during the execution of the application, CodeIgniter will check if any hooks are registered for that particular point. If there are, it will execute the corresponding functions.
The correct answer to the question “What are hooks in CodeIgniter?” would encompass the definition of hooks, their purpose, and their usage within the CodeIgniter framework.