Just starting to use CodeIgniter, and I\'d like to import some of my old classes for use in a new project. However, I don\'t want to modify them too much to fit into the CI
To do it codeigniter way, place your custom classes in libraries folder of codeigniter. And then use it by adding that class as library in your controller like this:
using in controller:
$this->load->library('someclass');
checkout complete article at http://www.codeigniter.com/user_guide/general/creating_libraries.html