<strong>一、 先安装vue-i18n</strong>

摘要：在vue的电商系统中我们需要支持多种语言切换，满足国际化需求。 vue-i18n是一个vue插件，主要作用就是让项目支持国际化多语言，使用方便快捷，能很轻松的将我们的项目国际化。主要介绍使用vue-i18n实现切换中英文效果。

一、 先安装vue-i18n

使用npm安装vue-i18n

npm install vue vue-i18n --save

二、 引入vue-i18n

在main.js里引入vue-i18n和相关用到的文件

import Vue from 'vue'

import 'babel-polyfill'

import 'normalize.css/normalize.css' // A modern alternative to CSS resets
import Element from 'element-ui'
import 'element-ui/lib/theme-chalk/index.css'

import UIComponents from 'ui-components'
import EnComponents from '@/components'
import VueAwesomeSwiper from 'vue-awesome-swiper'
import 'swiper/dist/css/swiper.css'

import '@/styles/index.scss' // global css
import App from './App'
import router from './router'
import store from './store'

import i18n from './lang' // Internationalization
import './icons' // icon
import './permission' // permission control
// 全局注册echarts、jsonp
import echarts from 'echarts'
import axios from 'axios'
// register global utility filters.
import * as filters from './filters' // global filter
// register global utility mixins.
import mixin from './utils/mixin'
import * as API_Common from './api/common'
import Cookies from 'js-cookie'

Vue.use(Element, {
  size: 'small',
  i18n: (key, value) => i18n.t(key, value)
})

Vue.use(UIComponents)
Vue.use(EnComponents)
Vue.use(VueAwesomeSwiper)

Vue.prototype.$echarts = echarts
Vue.prototype.$http = axios

Vue.prototype.$message.success = function(text) {
  Vue.prototype.$message({
    showClose: true,
    message: text,
    type: 'success',
    duration: 5000
  })
}
Vue.prototype.$message.error = function(text) {
  Vue.prototype.$message({
    showClose: true,
    message: text,
    type: 'error',
    duration: 5000
  })
}

Object.keys(filters).forEach(key => {
  Vue.filter(key, filters[key])
})

Vue.mixin(mixin)

Vue.config.productionTip = false
API_Common.getLanguage(Cookies.get('adminLanguage') || 'zh').then(response => {
  new Vue({
    el: '#app',
    beforeCreate() { this.$i18n.setLocaleMessage(Cookies.get('adminLanguage') || 'zh', response) },
    router,
    store,
    i18n,
    template: '<App/>',
    components: { App }
  })
}).catch(() => {
  Element.Message.error('设置语言失败，请刷新页面重试！')
  new Vue({
    el: '#app',
    router,
    store,
    i18n,
    template: '<App/>',
    components: { App }
  })
})

三、 从后台获取语言包数据

1.新建文件夹lang并在里index.js里引入vue-i18n并且创建带有选项的 VueI18n 实例

import Vue from 'vue'
import VueI18n from 'vue-i18n'
import Cookies from 'js-cookie'
Vue.use(VueI18n)

const messages = {
}

const i18n = new VueI18n({
  locale: Cookies.get('adminLanguage') || 'zh', // set locale
  messages // set locale messages
})

export default i18n

注意：文中有js-cookie 实例中加载了从后台请求过来的语言包

2.在vuex store里modules新建APP.js里切换的时候，根据语言加载各个国家的语言

import Cookies from 'js-cookie'
const app = {
  state: {
    sidebar: {
      opened: !+Cookies.get('adminSidebarStatus'),
      withoutAnimation: false
    },
    device: 'desktop',
    language: Cookies.get('adminLanguage') || 'zh'
  },
  mutations: {
    TOGGLE_SIDEBAR: state => {
      if (state.sidebar.opened) {
        Cookies.set('adminSidebarStatus', 1)
      } else {
        Cookies.set('adminSidebarStatus', 0)
      }
      state.sidebar.opened = !state.sidebar.opened
      state.sidebar.withoutAnimation = false
    },
    CLOSE_SIDEBAR: (state, withoutAnimation) => {
      Cookies.set('adminSidebarStatus', 1)
      state.sidebar.opened = false
      state.sidebar.withoutAnimation = withoutAnimation
    },
    TOGGLE_DEVICE: (state, device) => {
      state.device = device
    },
    SET_LANGUAGE: (state, language) => {
      state.language = language
      Cookies.set('adminLanguage', language)
    }
  },
  actions: {
    toggleSideBar({ commit }) {
      commit('TOGGLE_SIDEBAR')
    },
    closeSideBar({ commit }, { withoutAnimation }) {
      commit('CLOSE_SIDEBAR', withoutAnimation)
    },
    toggleDevice({ commit }, device) {
      commit('TOGGLE_DEVICE', device)
    },
    setLanguage({ commit }, language) {
      commit('SET_LANGUAGE', language)
    }
  }
}

export default app

3.在utils里新建文件转换router.meta.title，用于面包屑侧边栏标签视图

export function generateTitle(title) {
  return this.$t('route.' + title) // $t :this method from vue-i18n ,inject in @/lang/index.js
}

  4.在utils里新建文件request.js 在request方法里加 如果是刷新token或者登录，不需要检查token直接请求语言包

export default function request(options) {
  console.log(11, options)
  // 如果是刷新token或者登录，不需要检查token直接请求。
  if (options.url.indexOf('systems/admin-users/login') + options.url.indexOf('systems/admin-users/token') + options.url.indexOf('validator') + options.url.indexOf('language') > -4) {
    // console.log(options.url + ' | 请求的刷新token或是登录，不需要检查token直接请求。')
    return service(options)
  }
  return new Promise((resolve, reject) => {
    checkToken(options).then(() => {
      service(options).then(resolve).catch(reject)
    })
  })
}

四、根据vuex切换语言动态加载语言包

<script>
  import * as API_Common from '../../api/common'
  export default {
    computed: {
      language() {
        return this.$store.getters.language
      }
    },
    methods: {
      handleSetLanguage(lang) {
        API_Common.getLanguage(lang).then(async response => {
          this.$i18n.setLocaleMessage(lang, response)
          await this.$nextTick()
          this.$i18n.locale = lang //通过切换locale的值来实现语言切换
          this.$store.dispatch('setLanguage', lang)
          this.$message({
            message: lang === 'zh' ? '语言切换成功' : 'switch language success',
            type: 'success'
          })
        })
      }
    }
}
</script>

五、页面使用

{{$t('group.text1')}}
vue 组件form表单使用 :label="$t('group.text1')"