pb 如何根据数据库建立一棵动态树

long i,ll_handle

dw_tvdata.settransobject(sqlca)
dw_tvdata.retrieve()
tv_1.of_tv_insert('供应商列表','0',0,true,1)

FOR i=1 to dw_tvdata.rowcount()
of_tv_insert('['+dw_tvdata.object.SHFORM[i]+']'+dw_tvdata.object.sudesc[i],dw_tvdata.object.sucode[i],1,false,3)
next

//展开所有一级节点
ll_handle = tv_1.FindItem(RootTreeItem!,0)
tv_1.SetRedraw(false)
do until ll_handle <= 0
tv_1.ExpandItem(ll_handle)
ll_handle = tv_1.FindItem(NextTreeItem!,ll_handle)
loop
ll_handle = tv_1.FindItem(RootTreeItem!,0)
tv_1.SelectItem(ll_handle)
tv_1.SetRedraw(true)

【tv_1.of_tv_insert】
//一号，二号图片的插入
//argument:as_lable 显示值,al_data 数据值,ab_children 有无子项,as_lev 上级的句柄,就是本身的itemhandle
//ai_index 数组序号
treeviewitem ltvi_item
long ll_lev
ltvi_Item.label = as_label
ltvi_Item.data = al_data
ltvi_Item.pictureindex =al_pindex
ltvi_Item.selected