province:=treeview1.Selected.parent.Text;
area:=treeview1.Selected.Text;
adoquery1.SQL.Clear;
adoquery1.SQL.Add('select * from stuinfo where (省份=:a)and(地区=:b)');
adoquery1.Parameters.parambyname('a').value:=province;
adoquery1.Parameters.parambyname('b').value:=area;
adoquery1.Open;
area:=treeview1.Selected.Text;
adoquery1.SQL.Clear;
adoquery1.SQL.Add('select * from stuinfo where (省份=:a)and(地区=:b)');
adoquery1.Parameters.parambyname('a').value:=province;
adoquery1.Parameters.parambyname('b').value:=area;
adoquery1.Open;
ADOQUERY:PARAMETERS的参数b这个问题困扰了我很久了请大侠们一针见血
adoquery1.SQL.Clear;