React I18nify

Simple i18n translation and localization components and helpers for React.

A working example of this package can be found here at RunKit.

Migration guide

Upgrading to v6

react-i18nify v6 uses dayjs for date localization instead of date-fns, to make react-i18nify smaller and simpler to use. Migrating to this version requires the following changes to your project:

• Replace locale imports. E.g., import nl from 'date-fns/locale/nl'; needs to be replaced with import 'dayjs/locale/nl';
• Remove calls to addLocale and addLocales, these are not needed anymore.
• Update date formatting strings. For example, MM-dd-yyyy is now MM-DD-YYYY. See for more information the day.js documentation.

The v5 documentation can still be found here.

Installation

Install by using npm:

npm i react-i18nify

Getting started

Start by setting the translations and locale to be used:

import { setTranslations, setLocale } from 'react-i18nify';

setTranslations({
  en: {
    application: {
      title: 'Awesome app with i18n!',
      hello: 'Hello, %{name}!'
    },
    date: {
      long: 'MMMM do, yyyy'
    },
    export: 'Export %{count} items',
    export_0: 'Nothing to export',
    export_1: 'Export %{count} item',
    two_lines: <div>Line 1<br />Line 2<div>
  },
  nl: {
    application: {
      title: 'Toffe app met i18n!',
      hello: 'Hallo, %{name}!'
    },
    date: {
      long: 'd MMMM yyyy'
    },
    export: 'Exporteer %{count} dingen',
    export_0: 'Niks te exporteren',
    export_1: 'Exporteer %{count} ding',
    two_lines: <div>Regel 1<br />Regel 2</div>
  }
});

setLocale('nl');

Now you're all set up to unleash the power of react-i18nify!

Components

The easiest way to translate or localize in your React application is by using the Translate and Localize components:

import { Translate, Localize } from 'react-i18nify';

<Translate value="application.title" />
  // => Toffe app met i18n!
<Translate value="application.hello" name="Aad" />
  // => Hallo, Aad!
<Translate value="export" count={1} />
  // => Exporteer 1 ding
<Translate value="export" count={2} />
  // => Exporteer 2 dingen
<Translate value="two_lines" />
  // => <div>Regel 1<br />Regel 2</div>

<Localize value="07-2016-04" dateFormat="date.long" parseFormat="dd-yyyy-MM" />
  // => 7 april 2016
<Localize value="2015-09-03" dateFormat="date.long" />
  // => 3 september 2015
<Localize value="2015-09-03" dateFormat="distance-to-now" />
  // => 7 jaar geleden
<Localize value={10/3} options={{style: 'currency', currency: 'EUR', minimumFractionDigits: 2, maximumFractionDigits: 2}} />
  // => € 3,33

Helpers

If for some reason, you cannot use the components, you can use the translate and localize helpers instead:

import { translate, localize } from 'react-i18nify';

translate('application.title');
// => Toffe app met i18n!
translate('application.hello', { name: 'Aad' });
// => Hallo, Aad!'
translate('export', { count: 0 });
// => Niks te exporteren
translate('application.unknown_translation');
// => unknown_translation
translate('application', { name: 'Aad' });
// => {hello: 'Hallo, Aad!', title: 'Toffe app met i18n!'}

localize(1385856000000, { dateFormat: 'date.long' });
// => 1 december 2013
localize(Math.PI, { maximumFractionDigits: 2 });
// => 3,14
localize('huh', { dateFormat: 'date.long' });
// => null

If you want these helpers to be re-rendered automatically when the locale or translations change, you have to wrap them in a <I18n> component using its render prop:

import { I18n, translate } from 'react-i18nify';

<I18n render={() => <input placeholder={translate('application.title')} />} />;

Date localization

react-i18nify uses day.js internally to handle date localization. To reduce the base bundle size, day.js localizations are not loaded by default. If you need date localization, you can manually import them. For a list of available locales, refer to the day.js list of locales.

import 'dayjs/locale/en';
import 'dayjs/locale/nl';
import 'dayjs/locale/it';

API Reference

<Translate>

React translate component, with the following props:

• value (string)

The translation key to translate.

• Other props

All other provided props will be used as replacements for the translation.

<Localize>

React localize component, with the following props:

• value (number|string|object)

The number or date to localize.

• dateFormat (string)

The translation key for providing the format string. Only needed for localizing dates. For the full list of formatting tokens which can be used in the format string, see the day.js documentation.

• parseFormat (string)

An optional formatting string for parsing the value when localizing dates. For the full list of formatting tokens which can be used in the parsing string, see the day.js documentation.

• options (object)

When localizing numbers, the localize component supports all options as provided by the Javascript built-in Intl.NumberFormat object. For the full list of options, see https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/NumberFormat.

<I18n>

React I18n wrapper component, with the following prop:

• render (func)

The return value of the provide function will be rendered and automatically re-render when the locale or translations change.

setLocale(locale, rerenderComponents = true)

The used locale can be set with this function. By default, changing the locale will re-render all components. This behavior can be prevented by providing false as a second argument.

getLocale()

Get the currently used locale.

setTranslations(translations, rerenderComponents = true)

The used translations can be set with this function. By default, changing the translations will re-render all components. This behavior can be prevented by providing false as a second argument.

getTranslations()

Get the currently used translations.

setLocaleGetter(fn)

Alternatively to using setLocale, you can provide a callback to return the locale with setLocaleGetter:

import { setLocaleGetter } from 'react-i18nify';

const localeFunction = () => 'nl';

setLocaleGetter(localeFunction);

setTranslationsGetter(fn)

Alternatively to using setTranslations, you can provide a callback to return the translations with setTranslationsGetter:

import { setTranslationsGetter } from 'react-i18nify';

const translationsFunction = () => ({
  en: { ... },
  nl: { ... }
});

setTranslationsGetter(translationsFunction);

setHandleMissingTranslation(fn)

By default, when a translation is missing, the translation key will be returned in a slightly formatted way, as can be seen in the translate('application.unknown_translation'); example above. You can however overwrite this behavior by setting a function to handle missing translations.

import { setHandleMissingTranslation, translate } from 'react-i18nify';

setHandleMissingTranslation((key, replacements, options, err) => `Missing translation: ${key}`);

translate('application.unknown_translation');
// => Missing translation: application.unknown_translation

setHandleFailedLocalization(fn)

By default, when a localization failed, null will be returned, as can be seen in the localize('huh', { dateFormat: 'date.long' }); example above. You can however overwrite this behavior by setting a function to handle failed localizations.

import { setHandleFailedLocalization, localize } from 'react-i18nify';

setHandleFailedLocalization((value, options, err) => `Failed localization: ${value}`);

localize('huh', { dateFormat: 'date.long' });
// => Failed localization: huh

translate(key, replacements = {})

Helper function to translate a key, given an optional set of replacements. See the above Helpers section for examples.

localize(value, options)

Helper function to localize a value, given a set of options. See the above Helpers section for examples.

For localizing dates, the day.js library is used. A dateFormat option can be used for providing a translation key with the format string. For the full list of formatting tokens which can be used in the format string, see the day.js documentation. Moreover, parseFormat option can be used for providing a formatting string for parsing the value. For the full list of formatting tokens which can be used in the parsing string, see the day.js documentation.

For number formatting, the localize helper supports all options as provided by the Javascript built-in Intl.NumberFormat object. For the full list of options, see https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/NumberFormat.

t(key, replacements = {})

Alias for translate.

l(value, options)

Alias for localize.

forceComponentsUpdate()

This function can be called to force a re-render of all I18n components.

Example application with SSR

An example application with server-side rendering using features of react-i18nify can be found at https://github.com/sealninja/react-ssr-example.

License

MIT