如何用Vue3切换中英文显示举例说明

npm install vue-i18n

import { createApp } from 'vue';
import App from './App.vue';
import { createI18n } from 'vue-i18n';

// 定义翻译信息
const messages = {
  en: {
    welcome: 'Welcome',
    language: 'Language'
  },
  zh: {
    welcome: '欢迎',
    language: '语言'
  }
};

// 创建i18n实例
const i18n = createI18n({
  locale: 'en', // 默认语言
  fallbackLocale: 'en',
  messages,
});

const app = createApp(App);

// 使用i18n
app.use(i18n);
app.mount('#app');

<template>
  <div>
    <p>{{ $t('welcome') }}</p>
    <select v-model="currentLanguage" @change="changeLanguage">
      <option value="en">English</option>
      <option value="zh">中文</option>
    </select>
  </div>
</template>

<script>
export default {
  data() {
    return {
      currentLanguage: 'en'
    };
  },
  methods: {
    changeLanguage() {
      this.$i18n.locale = this.currentLanguage;
    }
  }
};
</script>

methods: {
  async changeLanguage() {
    const messages = await import(`./locales/${this.currentLanguage}.json`);
    this.$i18n.setLocaleMessage(this.currentLanguage, messages.default);
    this.$i18n.locale = this.currentLanguage;
  }
}