PHP CI框架自定义父控制器获取get、post参数可以带默认

<?php if (!defined('BASEPATH')) exit('No direct access allowed.');

    class Base_Controller extends CI_Controller {

        protected $GETDATA = NULL;
        protected $POSTDATA = NULL;

        public function __construct()
        {
            parent::__construct();

            header("Content-type: text/html; charset=utf-8");

            $this->GETDATA = $this->input->get();
            $this->POSTDATA = $this->input->post();

        }

        protected function GETDATA($key=NULL,$default=NULL)
        {
            return $this->RETURNDATA($this->GETDATA,$key,$default);
        }

        protected function POSTDATA($key=NULL,$default=NULL)
        {
            return $this->RETURNDATA($this->POSTDATA,$key,$default);
        }

        private function RETURNDATA($data,$key=NULL,$default=NULL)
        {

            if(empty($key))
            {
                return $data;
            }
            else
            {
                if(empty($data[$key]))
                {
                    if(!isset($default) || empty($default))
                    {
                        return "";
                    }
                    else
                    {
                        return $default;
                    }
                }
                else
                {
                    return $data[$key];
                }
            }
        }

    }


/* End of file MY_Controller.php */
/* Location: ./application/core/MY_Controller.php */

用法：
$this->GETDATA();//获取所有get参数
$this->GETDATA('test');//获取get参数中的test参数，不返回默认值
$this->GETDATA('test',0);//获取get参数中的test参数，返回默认值