1、基本用法

<script>
  export default {
    mounted() {
      this.timer = setInterval(() => { ... }, 1000);
    },
    beforeDestroy() {
      clearInterval(this.timer);
    }
  };
</script>

2、使用hook

<script>
  export default {
    mounted() {
      const timer = setInterval(() => { ... }, 1000);
      this.$once('hook:beforeDestroy', () => clearInterval(timer);)
    }
  };
</script>