多表查询：

$data['upvideos'] = $this->db->from('upload_video')->join('vcat', 'vcat.catid = upload_video.catid')->order_by('createtime', 'DESC')->get()->result_array();

跳转：

redirect('/uploadvideo/index', 'refresh');

访问方式：

define('IS_POST', strtolower($_SERVER["REQUEST_METHOD"]) == 'post');define('IS_GET', strtolower($_SERVER["REQUEST_METHOD"]) == 'get');