CodeIgniter: Payment Gateway using Authorize.net Library

First, download the Authorize.net library for CodeIgniter from here :
Download Authorize.net CodeIgniter Library »
Put the lib on your libraries directory, then load it as follow :


// Load authorize_net library
 $this->load->library('authorize_net'); 

// Invoke Authorize.net service 
$this->authorize_net->set_params($_POST); 

$this->authorize_net->set_login('$login_id', '$tran_key');

 $this->authorize_net->process(true); 

$response = $this->authorize_net->response();