How to calculate an IPv6 IP Number?

I'm adding GeoIP tracking to WCF Web Service using MaxMinds' GeoIP Lite Country. All works well for their IPv4 database but they don't give any samples to calculate an IPv6 IP Number. I've contacted them and they said to use a search engine.

Anyone have a sample they're willing to share? Any langu开发者_如何学Goage will do.

Its not a duplicate question per se, but from here:

There is no IPv4 to IPv6 mapping that is meaningful. things like 0.0.0.0 and 127.0.0.1 are special cases in the spec, so they have equivalent meaning. But given an IPv4 address it tells you nothing about what its specific IPv6 address would be. You can use a DNS lookup to see if a given IP address resolves to a host which in turn resolves to an IPv6 address in addition to an IPv4 address, but the DNS server would have to be configured to support that for the specific machine.