think\Model::getPk PHP Method

    public function getPk($name = '')
    {
        if (!empty($name)) {
            $table = $this->db()->getTable($name);
            return $this->db()->getPk($table);
        } elseif (empty($this->pk)) {
            $this->pk = $this->db()->getPk();
        }
        return $this->pk;
    }

 /**
 * +----------------------------------------------------------
 * 根据表单生成查询条件
 * 进行列表过滤
 * +----------------------------------------------------------
 * @access protected
 * +----------------------------------------------------------
 * @param \Think\Model $model 数据对象
 * @param array $map 过滤条件
 * @param string $sortBy 排序
 * @param boolean $asc 是否正序
 * +----------------------------------------------------------
 * @return void
     +----------------------------------------------------------
 * @throws \ThinkExecption
     +----------------------------------------------------------
 */
 protected function _list($model, $map, $sortBy = '', $asc = false, $countPk = 'id')
 {
     //排序字段 默认为主键名
     if (!empty($_REQUEST['_order'])) {
         $order = $_REQUEST['_order'];
     } else {
         $order = !empty($sortBy) ? $sortBy : $model->getPk();
     }
     //排序方式默认按照倒序排列
     //接受 sost参数 0 表示倒序 非0都 表示正序
     if (isset($_REQUEST['_sort'])) {
         //            $sort = $_REQUEST ['_sort'] ? 'asc' : 'desc';
         $sort = $_REQUEST['_sort'] == 'asc' ? 'asc' : 'desc';
         //[email protected]
     } else {
         $sort = $asc ? 'asc' : 'desc';
     }
     //取得满足条件的记录数
     $count = $model->where($map)->count($countPk);
     if ($count > 0) {
         import("@.ORG.Util.Page");
         //创建分页对象
         if (!empty($_REQUEST['listRows'])) {
             $listRows = $_REQUEST['listRows'];
         } else {
             $listRows = '';
         }
         $p = new Page($count, $listRows);
         //分页查询数据
         $voList = $model->where($map)->order("`" . $order . "` " . $sort)->limit($p->firstRow . ',' . $p->listRows)->select();
         //echo $model->getlastsql();
         //分页跳转的时候保证查询条件
         foreach ($map as $key => $val) {
             if (!is_array($val)) {
                 $p->parameter .= "{$key}=" . urlencode($val) . "&";
             }
         }
         //分页显示
         $page = $p->show();
         //列表排序显示
         $sortImg = $sort;
         //排序图标
         $sortAlt = $sort == 'desc' ? '升序排列' : '倒序排列';
         //排序提示
         $sort = $sort == 'desc' ? 1 : 0;
         //排序方式
         //模板赋值显示
         $this->assign('list', $voList);
         $this->assign('sort', $sort);
         $this->assign('order', $order);
         $this->assign('sortImg', $sortImg);
         $this->assign('sortType', $sortAlt);
         $this->assign("page", $page);
     }
     //[email protected]
     $this->assign('totalCount', $count);
     $this->assign('numPerPage', $p->listRows);
     $this->assign('currentPage', !empty($_REQUEST[C('VAR_PAGE')]) ? $_REQUEST[C('VAR_PAGE')] : 1);
     cookie('_currentUrl_', __SELF__);
     return;
 }