How to Redirect users based on their IP Address

Step 1 : Get the list of IPv4 ranges for the region of your choice (Look into www.apin.org for a beginning) and extract the ip's into a text file say call it ip.txt.

Step 2 : Get the IP address of the user and split it into an array with "." as the delimiter

Step 3 : Load the IP addresses from up.txt into a 2 dimensional array

Step 4 : Now for each IP range split the starting ip and ending ip into two arrays

Step 5 : Compare the corresponding numbers of the user ip array with those of the fromip and toip arrays

Step 6 : Repeat Step 4 thru Step 5 in a while loop till u reach the end of the array.

Now Go thru the snippet of code below and readthru the comments to understand it line by line.

<%
dim ipfromto(45,45)

yourip=split(request.ServerVariables("remote_addr"),".")


realpath=server.MapPath("./iponly.txt")


set myobj = server.CreateObject("scripting.filesystemobject")
set myfile = myobj.OpenTextFile(realpath)

i=1
while not myfile.atendofstream
line=myfile.readline
temp=split(line,"-")

ipfromto(i,1)=temp(0)
ipfromto(i,2)=temp(1)

i=i+1
wend
myfile.close


flag=false
j=1
While j< 46


'split the from-ip and to-ip based on "."
'fromip has the from ip address in four parts
'toip has the to ip address in four parts

fromip=split(ipfromto(j,1),".")
toip=split(ipfromto(j,2),".")
if yourip(0) > = fromip(0) and yourip(0) < = toip(0) then

if yourip(1) > = fromip(1) and yourip(1) < = toip(1) then

if yourip(2) > = fromip(2) and yourip(2) < = toip(2) then

if yourip(3) > = fromip(3) and yourip(3) < = toip(3) then

flag=true

end if

end if
end if

end if

if flag=true then
'Put your response.redirect() here
flag=false
else
'Put your response.redirect() here
end if

j=j+1
wend

%>

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