Uncaught (in promise) SyntaxError: Need to install with `app.use` function

这个错误提示是因为在使用vue-i18n时没有正确安装。根据引用\[1\]中的代码，你需要在Vue应用的入口文件中添加以下代码来正确安装vue-i18n：

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

const i18n = createI18n({
  locale: 'en',
  legacy: false,
  messages: {
    zh: { ...siphonI18n('zh') },
    en: { ...siphonI18n('en') }
  }
})

const app = createApp(App)
app.use(i18n)
app.mount('#app')

这样就可以正确安装vue-i18n并解决这个错误了。
#### 引用[.reference_title]
- *1* [Uncaught SyntaxError: Not available in legacy mode](https://blog.csdn.net/LQS5858/article/details/128343837)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v91^insert_down1,239^v3^insert_chatgpt"}} ] [.reference_item]
- *2* [从零开始Vue3+Element Plus后台管理系统(十五)——多语言国际化vue I18n](https://blog.csdn.net/immocha/article/details/130815114)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v91^insert_down1,239^v3^insert_chatgpt"}} ] [.reference_item]
- *3* [Uncaught (in promise) 的解决方法，可能原因](https://blog.csdn.net/qq_22701869/article/details/107816023)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v91^insert_down1,239^v3^insert_chatgpt"}} ] [.reference_item]
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