Check is valid ip/domain

Hey,
I at all do not understand ereg things. I want a function, which can check is string valid ip/host.

I mean
127.0.0.1 – valid
127.0.0.1.2 – invalid
1.server.com – valid
1.server.com/asdasd – invalid

I found something like this here:
[url]http://www.experts-exchange.com/Programming/Languages/Regular_Expressions/Q_24459252.html[/url]

But I am too nooby to fix it for me. So I asking for yours help ?

Thank you.

Also in #PHP _↴