text: import Vue from 'vue'
  import dayjs from 'dayjs'
  import 'dayjs/locale/zh-cn'
  import relativeTime from 'dayjs/plugin/relativeTime'
  dayjs.extend(relativeTime)
  dayjs.locale('zh-cn')
  const dayFormat = {}
  function isBrowser() {
      return typeof window !== 'undefined'
  }
  dayFormat.install = function (Vue) {
      const _dayjs = isBrowser() ? dayjs : function () { return Promise.resolve() }
      Vue.dayjs = _dayjs
      if (!Object.prototype.hasOwnProperty.call(Vue.prototype, '$dayjs')) {
          Object.defineProperty(Vue.prototype, '$dayjs', {
              get: function get() {
                  return _dayjs
              }
          })
      }
  }
  Vue.use(dayFormat)
  export default dayjs
  