+ +

Creating Ancillary Classes

+ +

In some cases you may want to develop classes that exist apart from your controllers but have the ability to +utilize all of Code Igniter's resources. This is easily possible as you'll see.

+ +

get_instance()

+ + +

Any class that you instantiate within your controller functions can access Code Igniter's native resources simply by using the get_instance() function. +This function returns the main Code Igniter object.

+ +

Normally, to call any of the available Code Igniter functions requires you to use the $this construct:

+ +


+$this->load->helper('url');

+$this->load->library('session');

+$this->config->item('base_url');

+etc.
+

+ +

$this, however, only works within your controllers, your models, or your views. +If you would like to use Code Igniter's classes from within your own custom classes you can do so as follows:

+ + +

First, assign the Code Igniter object to a variable:

+ +$obj =& get_instance(); + +

Once you've assigned the object to a variable, you'll use that variable instead of $this:

+ +


+$obj =& get_instance();


+$obj->load->helper('url');

+$obj->load->library('session');

+$obj->config->item('base_url');

+etc.
+

+ +

Note: You'll notice that the above get_instance() function is being passed by reference: +

+$obj =& get_instance(); +

+This is very important. Assigning by reference allows you to use the original Code Igniter object rather than creating a copy of it.

Code Igniter User Guide Version 1.4.0

Creating Ancillary Classes

get_instance()