Codeigniter load model in library

Question

I am using codeigniter 2.1.3

I am trying to load a model from the library. Initially my code in the construct in the library looks like this

$this->CI=& get_instance(); $this->CI->load->database('default')

Then in one of my library methods

when I tried the line below it doesnt work

$this->load->model('model_name')

but when I tried this

$this->CI->load->model('model_name','',TRUE)

it works, anyone can explain what the instance of CI refers to and the 2 extra parameters when loading the model? Thanks in advance.

Answer 1

A library is not necessarily a part of the way CodeIgniter works.

It could be a homemade library, to solve a task that you want done in your CI application.

This means that if you want to use any of CI's helpers, models or other libraries, you need to do this through the CI instance. This is achieved by doing this:

public function __construct()
{
    $this->CI =& get_instance();
}

By assigning the instance to your librarys member named CI, all CI related helpers, models and libraries can be loaded through $this->CI. By trying to do it only with $this you are only referring to the current library - not the CI instance.

To load your model correctly, in your library, $this->CI->load->model('model_name'); is enough. The second parameter allows you to access your model through a different object name. The third parameter is not necessary for loading models, but allows you to autoload the database driver.

If you want to access your model through the same member:

$respone = $this->CI->model_name->method();