I would like to match just the root of a URL and not the whole URL from a text string. Given:
http://www.youtube.co
A neat trick without using regular expressions:
var tmp = document.createElement ('a');
; tmp.href = "http://www.example.com/12xy45";
// tmp.hostname will now contain 'www.example.com'
// tmp.host will now contain hostname and port 'www.example.com:80'
Wrap the above in a function such as the below and you have yourself a superb way of snatching the domain part out of an URI.
function url_domain(data) {
var a = document.createElement('a');
a.href = data;
return a.hostname;
}