Using the Config object

The Config object is the primary interface to interact with the system configuration. You retrieve the Config object by calling the config() function like so:

$config = \Drupal::config('system.site'); 

This method returns a \Drupal\Core\Config\ImmutableConfig object that can only be used to read the configuration. If you need to modify the configuration, you can use the config.factory service, like so:

$config = \Drupal::service('config.factory')->getEditable('system.site'); 

To read attributes of the Config object, you can use the get() function, like:

$name = \Drupal::config('system.site')->get('name'); 

When retrieving nested configuration values, you can retrieve the full array of values using the get() function. For example, calling:

 $pages = \Drupal::config('system.site')->get('page'); 

Will return an array with each value from the mapping, like so:

[ 
  '403'   => 'url', 
  '404'   => 'url', 
  'front' => 'url', 
] 

If you want to retrieve a nested...