grant_str = nvll(dw_user_group.getitemstring(dw_user_group.getrow(),"menu_grant_" + string(ai_tab)),"")ls_max = left(grant_str,1)upperbound(ll_max_main_item.m_main.item[ai_tab])ll_main_item = 1ll_next = 1ll_main_count = 0ll_child_count = 0adw_menu.reset()do while ll_next <= ll_max_main_itemmenu_text.m_main.item[ai_tab][ll_next].ls_tag.m_main.item[ai_tab][ll_next]. = nvll(?????)nvll(?????)處有問題如何修改，其中nvll（）函數(shù)是自定義的意思類似profile函數(shù)如nvll(dw_1.getitemstring(l_index,col_name),"")