I18n class

Internationalization (i18n) middleware.

Provides translation support with:

Multiple locale support
Language detection from Accept-Language header, cookie, or query parameter
Variable interpolation: 'Hello {name}'
Pluralization support: {'one': '1 item', 'other': '{count} items'}
Fallback locale

Example

final translations = {
  'en': {
    'greeting': 'Hello, {name}!',
    'items': {'one': '1 item', 'other': '{count} items'},
  },
  'ja': {
    'greeting': 'こんにちは、{name}さん！',
    'items': {'other': '{count}個のアイテム'},
  },
};

app.use(I18n(translations));

app.get('/').handle((ctx) async {
  // Simple translation
  final greeting = ctx.t('greeting', {'name': 'John'});

  // Pluralization
  final items = ctx.t('items', {'count': 5});

  await ctx.res.json({'greeting': greeting, 'items': items});
});

Constructors

I18n(Translations translations, {String defaultLocale = 'en', List<String> supportedLocales = const [], String? cookieName = 'locale', String? queryParam = 'lang', LocaleResolver? localeResolver, bool detectFromHeader = true})

Creates an I18n middleware.

const

Properties

cookieName → String?

Cookie name for locale override.

final

defaultLocale → String

Default locale when detection fails.

final

detectFromHeader → bool

Whether to detect locale from Accept-Language header.

final