dayjs

mainjs

import dayjs from 'dayjs'
Vue.prototype.$dayJs = dayjs

页面

<span>{{ Time }}</span>

computed: {
    Time () {
      return this.$dayJs().format('YYYY-MM-DD HH:mm:ss')
    }
  },

<span>{{ time }}</span>

data(){
    return {
        timer: null,
        time: null,
            }
    },

mounted(){
 this.time = this.$dayJs().format('YYYY-MM-DD HH:mm:ss')
    this.timer = setInterval(() => {
      this.time = this.$dayJs().format('YYYY-MM-DD HH:mm:ss')
    }, 1000)
  },
  
 beforeDestroy () {
    if (this.timer) {
      clearInterval(this.timer)
    }
  }