检查来访ip是否合法的实际应用_asp技巧

sub chkIP(boardid)
      dim rsIP
      dim ipArr
      dim ignored
      dim i
      dim ip
      dim sql

      ip=Request.ServerVariables("REMOTE_ADDR")      
      ignored=false
      if not isempty(boardid) then      
         sql="select ignoreip from board where boardid="&cstr(boardid)
         set rsIP=conn.execute(sql)
         if not (rsIP.eof and rsIP.bof) then
            if instr(cstr(rsIP("ignoreip")&""),chr(13)&chr(10)) then
               iparr=split(rsIP("ignoreip"),chr(13)&chr(10))
               for i=0 to ubound(iparr)
                   if trim(iparr(i))<>"" and left(ip,len(trim(iparr(i))))=trim(iparr(i))  then
                      ignored=true
                      exit for
                   end if
               next
            else
               iparr=rsIP("ignoreip")
               if ip=trim(iparr) then
                  ignored=true
               end if
            end if
         end if
         rsIP.close
      end if
      if ignored then
         response.write "<script language=javascript>window.location.href=ignoreip.htm</script>"
      end if
  end sub