我有关于codeigniter超时的问题。
我知道config文件夹手动设置会话超时，如l

$config['sess_expiration']      = 123;

但我需要网站管理员管理会话超时动态到管理页面
请帮助我如何实现此逻辑
我试过这个逻辑，但没有工作

$this->session->sess_expiration = "120";

注意：在这里，我将数据库存储在值中。基于数据库值，我可以在中设置会话过期时间。
注1：$config['sess_time_to_update'] = 30;该值小于会话过期时间的
总逻辑代码：

public function edit($id)
    {
        Assets::add_css('../plugins/forms/uniform/uniform.default.css');
        Assets::add_css('../plugins/forms/select/select2.css');
        Assets::add_css('../plugins/forms/validate/validate.css');
        Assets::add_css('../plugins/misc/qtip/jquery.qtip.css');
        Assets::add_js('../plugins/charts/sparkline/jquery.sparkline.min.js');
        Assets::add_js('../plugins/forms/uniform/jquery.uniform.min.js');
        Assets::add_js('../plugins/forms/select/select2.min.js');
        Assets::add_js('../plugins/forms/validate/jquery.validate.min.js');
        Assets::add_js('../plugins/forms/wizard/jquery.bbq.js');
        Assets::add_js('../plugins/forms/wizard/jquery.form.js');
        Assets::add_js('../plugins/forms/wizard/jquery.form.wizard.js');
        Assets::add_module_js('setting','setting'); 
        if ($_POST)
       {
            $current_date = date("Y-m-d H:i:s");
            $data = array(
                            's_meta_value' => $this->input->post('s_meta_value'),
                            'updated_on' => $current_date
                          );
            $this->setting_model->session_mng_update($data,$id);
            $session_val=  $this->input->post('s_meta_value');
           if($session_val == 0)
           {
             $this->session->sess_expiration = '0';
           }
           else
           {          

            $this->session->sess_expiration = "120";
          // $val1 = $this->config->item('sess_expiration');
       // print_r($val1);
            //$session_seconds = ($session_val*60);
          $val2 = $this->config->set_item('sess_expiration',50);
          $this->session->CI_Session();
         //$val1=  $this->config->set_item('sess_expiration',50);
            $val3 = $this->config->item('sess_expiration');
             print_r($val3);exit;

           }

            Template::redirect('setting/setting/display');

        } 

       $val3 = $this->config->item('sess_expiration');
        print_r($val3);exit;
        $data = $this->setting_model->session_mng_edit($id);
        Template::set('page_title', 'Edit Session Management');
        Template::set('data', $data);
        Template::set_view('setting/session_management/edit_session_management');
        Template::render();       
}