Regex to extract subdomain from URL?

Question

I have a bunch of domain names coming in like this:

http://subdomain.example.com (example.com is always example.com, but the subdomain varies).

I need \"subd

Answer 1

To math sub domains with dot character in it, I used this one

https?:\/\/?(?:([^*]+)\.)?domain\.com

to get all matching characters after protocol until domain.

https://sub.domain.com (sub)

https://sub.sub.domain.com (sub.sub) ...