oracle数据库读取数据如下所示:
代码如下:
//构造节点 struct AREA { long id; long parent_area_id; string area_name; std::vector<AREA> children; } //从AREA表中根据id读一个结构体Area的数据 void Id2FindAreaTree(Session ses, AREA& Area, int id) { Statement select(ses); select << "SELECT id, parent_area_id,area_name FROM AREA where id =:pid", into(Area.id), into(Area.parent_area_id), into(Area.area_name), use(id), now; } //从AREA表中读取树形数据 void Parent_id2FindAreaTree(Session ses, std::vector<AREA>& vArea, int parent_id) { vArea.clear(); typedef Poco::Tuple<long, long, string> Area; typedef std::vector<Area> Are; Are ar; Statement select(ses); select << "SELECT id, parent_area_id,area_name FROM AREA where parent_area_id =:pid", into(ar), use(parent_id), now; Are::const_iterator it = ar.begin(); for (; it != ar.end(); ++it) { AREA area; area.id = it->get<0>(); area.parent_area_id = it->get<1>(); area.area_name = it->get<2>(); vArea.push_back(area); } } </span><pre name="code" class="cpp"><span style="font-size:14px;">//构建树结构(入口函数) Session 是POCO库中连接oracle的工具 void CDlg::CreateTreeCtrl(Session ses, long id, AREA& area, HTREEITEM hItem) { Id2FindAreaTree(ses, area, id); HTREEITEM hCurrItem = m_tree.InsertItem(area.area_name.c_str(), 0, 0, hItem, TVI_LAST); std::vector<AREA> temp; Parent_id2FindAreaTree(ses, temp, id); std::vector<AREA>::iterator it; for (it = temp.begin(); it != temp.end(); it++) { AREA a; CreateTreeCtrl(ses, it->id, a, hCurrItem); if (!a.area_name.empty()) { area.children.push_back(a); } } }</span> //最后,在初始化函数中,调用入口函数 AREA area; try { ODBC::Connector::registerConnector(); Session ses("ODBC", "UID=用户名;PWD=密码;DATABASE=数据库名;dsn=配置好的dsn"); CreateTreeCtrl(ses, 1, area, 0); ODBC::Connector::unregisterConnector(); } catch (ConnectionFailedException e) { }
结果如下图:
运行,大功告成了!觉得有用的朋友,记得点赞哦~
时间: 2024-10-25 19:03:37