Formatting

Named formatting

Locale messages:

const messages = {
  en: {
    message: {
      hello: '{msg} world'
    }
  }
}

Template:

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

Output:

<p>hello world</p>

List formatting

Locale messages:

const messages = {
  en: {
    message: {
      hello: '{0} world'
    }
  }
}

Template:

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

Output:

<p>hello world</p>

List formatting also accepts array-like objects:

<p>{{ $t('message.hello', {'0': 'hello'}) }}</p>

Output:

<p>hello world</p>

HTML formatting

Notice

⚠️ Dynamically localizing arbitrary HTML on your website can be very dangerous because it can easily lead to XSS vulnerabilities. Only use HTML interpolation on trusted content and never on user-provided content.

We recommended using the component interpolation feature.

Notice

🆕 8.11+

You can control the use of HTML formatting. see the detail warnHtmlInMessage constructor option and property API.

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

const messages = {
  en: {
    message: {
      hello: 'hello <br> world'
    }
  }
}

Template:

<p v-html="$t('message.hello')"></p>

Output (instead of the pre-formatted message )

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

Support ruby on rails i18n format

Locale messages:

const messages = {
  en: {
    message: {
      hello: '%{msg} world'
    }
  }
}

Template:

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

Output:

<p>hello world</p>

Custom formatting

Sometimes, you may need to translate using custom formatting (e.g. ICU message syntax).

You can do that with a custom formatter that implements the Formatter Interface.

The following custom formatter with ES2015 class syntax:

// Custom Formatter implementation
class CustomFormatter {
     constructor (options) {
       // ...
     }

     //
     // interpolate
     //
     // @param {string} message
     //   string of list or named format.
     //   e.g.
     //   - named formatting: 'Hi {name}'
     //   - list formatting: 'Hi {0}'
     //
     // @param {Object | Array} values
     //   values of `message` interpolation.
     //   passed values with `$t`, `$tc` and `i18n` functional component.
     //   e.g.
     //   - $t('hello', { name: 'kazupon' }) -> passed values: Object `{ name: 'kazupon' }`
     //   - $t('hello', ['kazupon']) -> passed values: Array `['kazupon']`
     //   - `i18n` functional component (component interpolation)
     //     <i18n path="hello">
     //       <p>kazupon</p>
     //       <p>how are you?</p>
     //     </i18n>
     //     -> passed values: Array (included VNode):
     //        `[VNode{ tag: 'p', text: 'kazupon', ...}, VNode{ tag: 'p', text: 'how are you?', ...}]`
     //
     // @return {Array<any>}
     //   interpolated values. you need to return the following:
     //   - array of string, when is using `$t` or `$tc`.
     //   - array included VNode object, when is using `i18n` functional component.
     //
     interpolate (message, values) {
       // implement interpolation logic here
       // ...

       // return the interpolated array
       return ['resolved message string']
     }
}

// register with `formatter` option
const i18n = new VueI18n({
  locale: 'en-US',
  formatter: new CustomFormatter(/* here the constructor options */),
  messages: {
    'en-US': {
      // ...
    },
    // ...
  }
})

// Run!
new Vue({ i18n }).$mount('#app')

You can check the custom formatter official example.

Last Updated: 10/3/2019, 11:23:38 AM