Hooks
Hooks in CodeIgniter allow you to modify the behavior of the framework without modifying core files. This is accomplished by calling a set of user-defined functions at certain points in the execution of the framework. Hooks can be used for various purposes such as modifying inputs, output, and final rendered output.
Syntax
The syntax for Hook in CodeIgniter is as follows:
$hook['pre_controller'] = array(
'class' => 'MyClass',
'function' => 'Myfunction',
'filename' => 'Myclass.php',
'filepath' => 'hooks'
);
Example
To create a hook after loading a library, create a PHP file in the application/hooks
directory with the following code:
class MyHook
{
public function do_something()
{
// Some code here
}
}
Then, in the application/config/config.php
file, add the following code under the "Hooks" section:
$config['enable_hooks'] = TRUE;
$hook['post_controller_constructor'][] = array(
'class' => 'MyHook',
'function' => 'do_something',
'filename' => 'MyHook.php',
'filepath' => 'hooks'
);
Explanation
In the above example, the MyHook
class has a method named do_something
which will be called when the hook is triggered. The hook is defined under the "Hooks" section in the config.php
file and specifies the class name, method name, filename, and filepath of the hook.
In this example, the hook is defined to run after the controller constructor has been called. This hook will call the do_something
method in the MyHook
class.
Use
Hooks in CodeIgniter can be used for various purposes such as modifying inputs, output, and final rendered output. Hooks can be used to perform pre and post actions associated with framework execution. Common use cases include logging, modifying data, and implementing security checks.
Important Points
- Hooks are executed in the order they are defined in the
config.php
file. - Multiple hooks can be defined for the same hook point.
- Hooks can be enabled or disabled globally using the
enable_hooks
configuration parameter.
Summary
Hooks in CodeIgniter allow you to modify the behavior of the framework without modifying core files. Hooks can be used for various purposes such as modifying inputs, output, and final rendered output. Hooks can be enabled or disabled globally, and are executed in the order they are defined in the config.php
file.