public function addDepartment()
 {
     $this->checkLogin();
     $Department = new DepartmentModel();
     $data = $_POST;
     $data['DP_psd'] = md5($data['DP_psd']);
     $result = $Department->addDepartment($data);
     if ($result == true) {
         $this->success('添加成功', 'index');
     } else {
         $this->error("添加失败");
     }
 }