Best practice javascript and multilanguage

Question

what is the best practice for multilanguage website using DOM Manipulating with javascript? I build some dynamic parts of the website using javascript. My first thought was

Answer 1

There are are a few things you need to keep in mind when designing multilanguage support:

1 - Separate code from data (i.e. don't hard-code strings right into your functions)

2 - create a formatting hook function to deal with localization differences. Allowing formattable strings ("{0}") is better than concatenating ("Welcome to" + value), for a lot of reasons:

• in some languages, a number is formatted like 1.234.678,00 instead of 1,234,567.00
• pluralization is often not as simple as appending an "s" at the end of the singular
• grammar rules are different and can affect the order of things so you should allow dynamic data to be appended after the translation hook: for example, "Welcome to {0}" turns into "{0} he youkoso" in japanese (this happens in pretty much every language, mind you).

3 - Make sure that you can actually format strings after the translation hook runs, so you can reuse keys.

4 - Do not, under any circunstance, hook database outputs to the translator utility. If you have multilingual data, create separate tables / rows in your database. I've seen people get this no-brainer wrong fairly often (usually for countries and states/provinces in forms).

5 - Create explicit coding practices rules for creating keys. The formatter utility function (which will look something like translate("hello world") will take a key as a parameter, and keys with slight variations make maintainance very annoying. For instance, you might end up with three keys in the following example: "enter you name", "enter your name:", "enter your name: ". Choose one format (e.g. no colon, trimmed) and catch discrepancies in code reviews. Don't do this filtering programmatically, as it can trigger false positives.

6 - Be mindful that HTML markup could potentially be needed in the translation table (e.g. if you need to bold a word in a sentence, or have footnote medical references). Test for this extensively.

7 - There are several ways of importing language strings. Ideally, you should have multiple versions of a language.lang.js file, switch between them with server side code, and reference the file from the bottom of the HTML file. Pulling the file via AJAX is also an alternative, but could introduce delays. Merging language.js into your main code file is not advisable, since you lose the benefits of file caching.

8 - Test with your target languages. This sounds silly, but I've seen a serious bug once because the programmer didn't bother to check for the existence of "é" in the key.