data () {
    return {
      timer : null
    }
  },
  beforeDestroy () {
    let that = this;
    clearInterval(that.timer);
    that.timer = null;
  },
  destroyed () {
    let that = this;
    clearInterval(that.timer);
    that.timer = null;
  },
  mounted () {
    let that = this;
    that.timer = window.setInterval(() => {
      setTimeout(() => {
        that.getData()
      }, 0)
    },1000)
  },