VB ip限制访问代码

<%
function IP2Num(sip)
 dim str1,str2,str3,str4
 dim num
 IP2Num=0
 if isnumeric(left(sip,2)) then
  str1=left(sip,instr(sip,".")-1)
  sip=mid(sip,instr(sip,".")+1)
 
  str2=left(sip,instr(sip,".")-1)
  sip=mid(sip,instr(sip,".")+1)
  str3=left(sip,instr(sip,".")-1)
  str4=mid(sip,instr(sip,".")+1)
  num=cint(str1)*256*256*256+cint(str2)*256*256+cint(str3)*256+cint(str4)-1
  IP2Num = num
 end if
end function

function Num2IP(nip)
 iip1 = int(nip/256/256/256)
 iip2 = int((nip-iip1*256*256*256)/256/256)
 iip3 = int((nip-iip1*256*256*256-iip2*256*256)/256)
 iip4 = int((nip-iip1*256*256*256-iip2*256*256-iip3*256) mod 256)
 iip0 = iip1 &"."& iip2 & "." &iip3 &"."& iip4
 Num2IP = iip0
end function

userIPnum = IP2Num(Request.ServerVariables("REMOTE_ADDR"))
dim ip