加兩個字段,一個是父ID,如果是頂層,父ID就為0,一個是是否有下級,0元1有,一個函數就可解決,在函數中間調用本函數,找出了父層,再找他是否有下級,如果有,再找父ID為本ID的欄目

'==================================================
'過程名：listecityclass
'作  用：顯示系統分類
'參  數：id ------ 要匹配的系統ID
'==================================================
  Sub listecityclass(id)
    dim F_reco,F_total,F_n,F_classid,F_classname,F_classlayer
    set F_reco=Server.CreateObject("ADODB.Recordset")
    F_reco.Open "select classid,classname,classlayer from ws_ecityclass where classparent=0 and classlist=0 order by classorder Asc",conn,1,1
    F_total=F_reco.recordcount
    if F_total>0 then
      for F_n=1 to F_total
        format_i=1
    F_classid=F_reco(0)
    F_classname=F_reco(1)
    F_classlayer=F_reco(2)
        response.write "<option"
        if F_classlayer=0 then response.write " value=" & F_classid
        if id=F_classid then response.write " selected"
        response.write ">" & F_classname & "</option>"
        if F_classlayer=1 then call listecityclass_(id,F_classid)  '調用另一個函數,在下面
        F_reco.movenext
      next
    end if
    F_reco.close : set F_reco=nothing
  End Sub
  Sub listecityclass_(id,iid)
    dim F_reco,F_total,F_n,F_m,F_classid,F_classname,F_classlayer
    set F_reco=Server.CreateObject("ADODB.Recordset")
    F_reco.Open "select classid,classname,classlayer from ws_ecityclass where classparent="&iid&" and classlist=0 order by classorder Asc",conn,1,1
    F_total=F_reco.recordcount
    if F_total>0 then
      for F_n=1 to F_total
    F_classid=F_reco(0)
    F_classname=F_reco(1)
    F_classlayer=F_reco(2)
        format_i=format_i+1
        response.write "<option"
        if F_classlayer=0 then response.write " value=" & F_classid
        if id=F_classid then response.write " selected"
        response.write ">"
        for F_m=format_i to 2 step -1
          response.write "&nbsp;&nbsp;"
          if F_m=2 then
            if F_n=F_total then response.write "└" else response.write "├"
      end if
        next
        response.write F_classname & "</option>"
        if F_classlayer=1 then call listecityclass_(id,F_classid) '調用本函數
        F_reco.movenext
        format_i=format_i-1
      next
    end if
    F_reco.close : set F_reco=nothing
  End Sub