Compatibility

• Vue.js 1.0.0+

Installation

npm

$ npm install vue-i18n

When used in CommonJS, you must explicitly install the router via Vue.use():

var Vue = require('vue')
var VueI18n = require('vue-i18n')

Vue.use(VueI18n)
Vue.config.lang = 'ja'
Vue.locale('ja', { ... })

Usage

var Vue = require('vue')
var VueI18n = require('vue-i18n')

// ready translated locales
var locales = {
  en: {
    message: {
      hello: 'hello world'
    }
  },
  ja: {
    message: {
      hello: 'こんにちは、世界'
    }
  }
}

// install plugin
// DEPRECATED:
//   `options` arguments, please use `Vue.config.lang` and `Vue.locale`.
//   3.1 or later, not used `options` arguments!!
Vue.use(VueI18n/*, {
  lang: 'ja',
  locales: locales
}*/)


// set lang
// RECOMMEND: 3.0 or later
Vue.config.lang = 'ja'

// set locales
// RECOMMEND: 3.0 or later
Object.keys(locales).forEach(function (lang) {
  Vue.locale(lang, locales[lang])
})

// create instance
new Vue({ el: 'body' })

Template the following:

<p>{{ $t("message.hello") }}</p>

Output the following:

<p>こんにちは、世界</p>

Formatting

HTML formatting

In some cases you might want to rendered your translation as an HTML message and not a static string.

var locales = {
  en: {
    message: {
      hello: 'hello <br> world'
    }
  }
}

Template the following (notice the tripple brackets):

<p>{{{ $t('message.hello') }}}</p>

Output the following (instead of the message pre formatted)

<p>hello
<!--<br> exists but is rendered as html and not a string-->
world</p>

Named formatting

Locale the following:

var locales = {
  en: {
    message: {
      hello: '{msg} world'
    }
  }
}

Template the following:

<p>{{ $t('message.hello', { msg: "hello"}) }}</p>

Output the following:

<p>hello world</p>

List formatting

Locale the following:

var locales = {
  en: {
    message: {
      hello: '{0} world'
    }
  }
}

Template the following:

<p>{{ $t('message.hello', ["hello"]) }}</p>

Output the following:

<p>hello world</p>

Support ruby on rails i18n format

Locale the following:

var locales = {
  en: {
    message: {
      hello: '%{msg} world'
    }
  }
}

Template the following:

<p>{{ $t('message.hello', { msg: "hello"}) }}</p>

Output the following:

<p>hello world</p>

Dynamic locale

Sometimes, you need to set dynamically the locale from external location. You can set dynamically it with Vue.locale.

the below the example:

var self = this
var lang = 'ja'
Vue.locale(lang, function () {
  self.loading = true
  return fetch('/locale/' + lang, {
    method: 'get',
    headers: {
      'Accept': 'application/json',
      'Content-Type': 'application/json'
    }
  }).then(function (res) {
    return res.json()
  }).then(function (json) {
    self.loading = false
    if (Object.keys(json).length === 0) {
      return Promise.reject(new Error('locale empty !!'))
    } else {
      return Promise.resolve(json)
    }
  }).catch(function (error) {
    self.error = error.message
    return Promise.reject()
  })
}, function () {
  Vue.config.lang = lang
})

Dynamic locale interfaces

In dynamic locales, You can use the two type interfaces:

1. function

You need to implement locale setting that return function have function (resolve, reject) like promise (future). The following, those argument of the function, if successful, you need to use the resolve according to locale object. if failed, you need to use reject

• successful: resolve
• failed: reject

2. promise

As mentioned above, You need to implement locale setting that return a promise. if successful, you need to resolve according to locale object. if failed, you need to use reject.

API References

Global Config

lang

• Type: String

• Default: en

• Usage:

  Get or set a translation language code. Default by en string value.

  Vue.config.lang = 'ja'
  

Global Methods

Vue.locale ( lang, [locale], [cb] )

• Arguments:

  • {String} lang
  • {Object | Function} [locale]
  • {Function} [cb]

• Return:

  • locale function or object

• Usage:

  Register or retrieve a locale

  // register locale with object
  Vue.locale('en', { message: 'hello' })
  
  // register with external locale
  Vue.locale('ja', function () {
    return fetch('/locales/ja', {
      method: 'get',
      // ...
    }).then(function (json) {
      return Promise.resolve(json)
    }).catch(function (error) {
      return Promise.reject()
    })
  }, function () {
    Vue.config.lang = 'ja'
  })
  

Vue.t( keypath, [lang], [arguments] )

• Arguments:

  • {String} keypath
  • {String} [lang]
  • {Array | Object [arguments]

• Return: Translated string

• Usage: This is the same as the $t method. This is translate function for global. more detail see $t

Instance Methods

$t(keypath, [lang], [arguments])

• Arguments:

  • {String} keypath
  • {String} [lang]
  • {Array | Object [arguments]

• Return: Translated string

• Usage: Translate the locale of keypath. If you specified lang, translate the locale of lang. If you specified keypath of list / named formatting local, you must specify arguments too. For arguments more details see Formatting.

Options

NOTE: Deprecated in 3.1 or later ⚠️

Plugin options

Vue.use(plugin, {
  lang: 'en',
  locales: {
    en: {
      ...
    },
    ...
    ja: {
      ...
    }
  }
})

lang

Specify translate the language code.

If you abbreviated the lang option, translate as well as 'en' language code option (default: 'en').

locales

Specify translate some local dictionary.

If you abbreviated the locales option, set the empty local dictionary.