JavaScript for detecting browser language preference [duplicate]

Answer 1

I have a hack that I think uses very little code and is quite reliable.

Put your site's files in a subdirectory. SSL into your server and create symlinks to that subdirectory where your files are stored that indicate your languages.

Something like this:

ln -s /var/www/yourhtml /var/www/en
ln -s /var/www/yourhtml /var/www/sp
ln -s /var/www/yourhtml /var/www/it

Use your web server to read HTTP_ACCEPT_LANGUAGE and redirect to these "different subdirectories" according to the language value it provides.

Now you can use Javascript's window.location.href to get your url and use it in conditionals to reliably identify the preferred language.

url_string = window.location.href;
if (url_string = "http://yoursite.com/it/index.html") {
    document.getElementById("page-wrapper").className = "italian";
}

Answer 2

var language = window.navigator.userLanguage || window.navigator.language;
alert(language); //works IE/SAFARI/CHROME/FF

window.navigator.userLanguage is IE only and it's the language set in Windows Control Panel - Regional Options and NOT browser language, but you could suppose that a user using a machine with Window Regional settings set to France is probably a French user.

navigator.language is FireFox and all other browser.

Some language code: 'it' = italy, 'en-US' = english US, etc.

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As pointed out by rcoup and The WebMacheter in comments below, this workaround won't let you discriminate among English dialects when users are viewing website in browsers other than IE.

window.navigator.language (Chrome/FF/Safari) returns always browser language and not browser's preferred language, but: "it's pretty common for English speakers (gb, au, nz, etc) to have an en-us version of Firefox/Chrome/Safari." Hence window.navigator.language will still return en-US even if the user preferred language is en-GB.

Answer 3

I had the same problem, and I wrote the following front-end only library that wraps up the code for multiple browsers. It's not much code, but nice to not have to copy and paste the same code across multiple websites.

Get it: acceptedlanguages.js

Use it:

<script src="acceptedlanguages.js"></script>
<script type="text/javascript">
  console.log('Accepted Languages:  ' + acceptedlanguages.accepted);
</script>

It always returns an array, ordered by users preference. In Safari & IE the array is always single length. In FF and Chrome it may be more than one language.

Answer 4

navigator.userLanguage for IE

window.navigator.language for firefox/opera/safari

Answer 5

Javascript way:

var language = window.navigator.userLanguage || window.navigator.language;//returns value like 'en-us'

If you are using jQuery.i18n plugin, you can use:

jQuery.i18n.browserLang();//returns value like '"en-US"'

Answer 6

DanSingerman has a very good solution for this question.

The only reliable source for the language is in the HTTP-request header. So you need a server-side script to reply the request-header or at least the Accept-Language field back to you.

Here is a very simple Node.js server which should be compatible with DanSingermans jQuery plugin.

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end(JSON.stringify(req.headers));
}).listen(80,'0.0.0.0');