请问如何做出有层次结点的树形菜单?
请问如何做出有层次结点的树形菜单? 我的数据库表中结构如下:

id upid title

1 0 A组

2 1 A001

3 1 A002

4 0 B组

5 4 B001

6 4 B002

...


要求树形菜单形式为:

A组

A001

A002

B组

B001

B002

...


请问谁有这个示例呢? 万分谢谢


[解决办法]
<%
set rsb=conn.execute( "select * from tree where upid=0 ")
while not rsb.eof
response.write(rsb( "title "))
set rss=conn.execute( "select * from tree where upid= "&rsb( "upid "))
while not rss.eof
response.write(rss( "title "))
rss.movenext
wend
set rss=nothing
rsb.movnext
wend
set rsb=nothing
%>
[解决办法]
建议数据库结构改一下,否则循环嵌套查询估计效率会比较低,而且数据库压力也会比较大,当然,如果数据少就看你改数据结构方便不方便了

id upid title

1 0 A组

2 1 A001

3 1 A002

4 0 B组

5 4 B001

6 4 B002

改成:
id upid title flag

1 0 A组 1

2 1 A001 1

3 1 A002 1

4 0 B组 2

5 4 B001 2

6 4 B002 2

这样就可以用一条简单的语句查询出效果
dim pre
dim sql,rs

sql= "select id,title from forum_type where upid=0 order by flag,upid "
set rs=server.createObject( "adodb.recordset ")
rs.open sql,conn,1,1
if not rs.eof and not rs.bof then
do while not rs.eof
if upid=0 then
pre= " "
else
pre= "     "
end if
Response.Write pre&rs(1)& " <br> "
rs.movenext
loop
else
Response.Write "没有任何菜单 "
end if
rs.close
set rs=nothing