npm install vue-i18n

export default {
  home: {
    helloworld: "hello workd ！"
  }
};

export default {
  home: {
    helloworld: "你好世界"
  }
};

import Vue from "vue";
import VueI18n from "vue-i18n";
import enLocale from "./en";
import zhLocale from "./zh";
Vue.use(VueI18n);
const i18n = new VueI18n({
  locale: localStorage.lang || "zh",
  messages: {
    en: {
      ...enLocale
    },
    zh: {
      ...zhLocale
    }
  }
});
export default i18n;

import Vue from "vue";
import App from "./App.vue";
import router from "./router";
import store from "./store";
import i18n from "./assets/i18n/index";
Vue.config.productionTip = false;
Vue.prototype.$i18n = i18n;
new Vue({
  router,
  store,
  i18n,
  render: h => h(App)
}).$mount("#app");

<template>
  <div class="about">
    <h1>{{ $t("home.helloworld") }}</h1>
    <button @click="changeLang()">切换英文</button>
    <p>{{hi}}</p>
  </div>
</template>
 
<script>
export default {
  data: function() {
    return {};
  },
  computed: {
    hi() {
      return this.$t("home.helloworld");
    }
  },
  methods: {
    changeLang() {
      this.$i18n.locale = "en";
    }
  }
};
</script>