Getting the user's region with navigator.language
Your solution is based on the false premise that the browser's language tag reliably matches the user's country. E.g., I have set my browser language to German, even though I am living nowhere near Germany at the moment, but rather in the United States.
Also, for example in Chrome, many language packs do not require you to specify the region modifier. Setting Chrome's display language to German
provides the following language tag:
> navigator.language< "de"No region tag at all, and a fairly common language.
Bottom line is, my browser setup results in language tag de, even though I live in the United States.
A more accurate and possibly reliable way to determine the user's location would be to derive it from the IP address associated with the request. There are numerous services that offer this service. ip-api.com is one of them:
$.get("http://ip-api.com/json", function(response) { console.log(response.country); // "United States" console.log(response.countryCode); // "US"}, "jsonp");<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
Regex found here: https://github.com/gagle/node-bcp47/blob/master/lib/index.js
var re = /^(?:(en-GB-oed|i-ami|i-bnn|i-default|i-enochian|i-hak|i-klingon|i-lux|i-mingo|i-navajo|i-pwn|i-tao|i-tay|i-tsu|sgn-BE-FR|sgn-BE-NL|sgn-CH-DE)|(art-lojban|cel-gaulish|no-bok|no-nyn|zh-guoyu|zh-hakka|zh-min|zh-min-nan|zh-xiang))$|^((?:[a-z]{2,3}(?:(?:-[a-z]{3}){1,3})?)|[a-z]{4}|[a-z]{5,8})(?:-([a-z]{4}))?(?:-([a-z]{2}|\d{3}))?((?:-(?:[\da-z]{5,8}|\d[\da-z]{3}))*)?((?:-[\da-wy-z](?:-[\da-z]{2,8})+)*)?(-x(?:-[\da-z]{1,8})+)?$|^(x(?:-[\da-z]{1,8})+)$/i;let foo = re.exec('de-AT'); // German in Austrialet bar = re.exec('zh-Hans-CN'); // Simplified Chinese using Simplified script in mainland Chinaconsole.log(`region ${foo[5]}`); // 'region AT'console.log(`region ${bar[5]}`); // 'region CN'
In Firefox, you can choose your language settings in preferences:
The list of languages has 269 items, 192 of which do not include any region code.
The region is only useful when a language has different variants depending on the location. This way users can tell the server in which language variant they prefer the response to be.
Do not use this approach to locate the user. It's too unreliable, because the user may not specify any region, or because the user could physically be in another place.
If you want to locate the user, you should use the Geolocation API.