asp 根据IP地址自动判断转向分站的代码

'====================================
'得到客户端的IP转换成长整型，返回值getIpvalue
Function getIpvalue(clientIP)
On Error Resume Next
Dim strIp, array_Ip
strIp=0
array_Ip = Split(clientIP,".")
If UBound(array_Ip)<>3 Then
getIpvalue=0
Exit Function
End If
For i=0 To 3
strIp=strIp+(CInt(array_Ip(i))*(256^(3-i)))
Next
getIpvalue=strIp
If Err Then getIpvalue=0
End Function
'==================================
clientIP=request.ServerVariables("REMOTE_HOST")
IpValue=getIpvalue(clientIP)
strSql="select top 1 City from [Ipaddress] where "&IpValue&"
between Ip1 and Ip2"
Set RsIp=conn.execute(strSql)
If RsIp.bof and RsIp.eof then
UrlCity="未知"
Else
UrlCity=RsIp.Fields.Item("City").Value
End If
if instr(UrlCity,"广州")<>0 then
response.Redirect("http://www.jb51.net")
end if
if instr(UrlCity,"深圳")<>0 then
response.Redirect("http://img.jb51.net")
end if
if instr(UrlCity,"上海")<>0 then
response.Redirect("http://sh.jb51.net")
end if
'所用到的IP数据库可以去网上down一个