Javascript splitting string using only last splitting parameter

Question

An example of what im trying to get:

String1 - 'string.co.uk' - would return 'string' and 'co.uk'
String2 - 'random.words.string.co.uk' - would return 'string` and 'co.uk'

I currently have this:

var split= [];
var tld_part = domain_name.split(".");
var sld_parts = domain_name.split(".")[0];
tld_part = tld_part.slice(1, tld_part.length);
split.push(sld_parts);
split.push(tld_part.join("."));

With my current code, it takes the split parameter from the beginning, i want to reverse it if possible. With my current code it does this:

String1 - 'string.co.uk' - returns 'string' and 'co.uk'
String2 - 'random.words.string.co.uk' - would return 'random` and 'words.string.co.uk'

Any suggestions?

Answer 1

To expand upon elclanrs comment:

function getParts(str) {
    var temp = str.split('.').slice(-3) // grabs the last 3 elements
    return {
        tld_parts : [temp[1],temp[2]].join("."),
        sld_parts : temp[0]
    }
}

getParts("foo.bar.baz.co.uk") would return { tld_parts : "co.uk", sld_parts : "baz" }

and

getParts("i.got.99.terms.but.a.bit.aint.one.co.uk") would return { tld_parts : "co.uk", sld_parts : "one" }

Answer 2

One way that comes to mind is the following

var tld_part = domain_name.split(".");
var name = tld_part[tld_part.length - 2];
var tld = tld_part[tld_part.length - 1] +"."+ tld_part[tld_part.length];

Answer 3

try this

var str='string.co.uk'//or 'random.words.string.co.uk'
var part = str.split('.');
var result = part[part.length - 1].toString() + '.' + part[part.length - 1].toString();
alert(result);

Answer 4

Depending on your use case, peforming direct splits might not be a good idea — for example, how would the above code handle .com or even just localhost ? In this respect I would go down the RegExp route:

function stripSubdomains( str ){
  var regs; return (regs = /([^.]+)(\.co)?(\.[^.]+)$/i.exec( str ))
    ? regs[1] + (regs[2]||'') + regs[3]
    : str
  ;
};

Before the Regular Expression Police attack reprimand me for not being specific enough, a disclaimer:

The above can be tightened as a check against domain names by rather than checking for ^. , to check for the specific characters allowed in a domain at that point. However, my own personal perspective on matters like these is to be more open at the point of capture, and be tougher from a filtering point at a later date... This allows you to keep an eye on what people might be trying, because you can never be 100% certain your validation isn't blocking valid requests — unless you have an army of user testers at your disposal . At the end of the day, it all depends on where this code is being used, so the above is an illustrated example only.