How to get domain name only using javascript?

Question

I want to get domain name only using javascript. Ex

vn.search.yahoo.com -> yahoo
vn.search.yahoo.com.vn -> yahoo
sub1.sub2.sub3.abcdef.co.uk -> abcd         


        

Answer 1

I was looking for something that would work for the majority of cases, without having to maintain the TLD list (and skip it's size!). It seems to me that you can do this pretty accurately by looking instead at the Second-Level Domain for common ones:

function getDomainName(domain) {
    var parts = domain.split('.').reverse();
    var cnt = parts.length;
    if (cnt >= 3) {
        // see if the second level domain is a common SLD.
        if (parts[1].match(/^(com|edu|gov|net|mil|org|nom|co|name|info|biz)$/i)) {
            return parts[2] + '.' + parts[1] + '.' + parts[0];
        }
    }
    return parts[1]+'.'+parts[0];
}

Fiddle & Tests @ http://jsfiddle.net/mZPaf/2/

Critiques/thoughts welcome.