vue定时器清除不掉,导致功能频繁执行问题

clearInterval(this.timer)//使用前先清空定时器
this.timer = setInterval(()=>{
    console.log(1)
}, 1000)

if(!window.timer){ window.timer = []}
// 将存起来的定时器一并清除
window.timer.map(item=>{
    clearInterval(item)
})
const timerId = setInterval(()=>{
    console.log(1)
}, 1000)
window.timer.push(timerId)

setInterval(code, milliseconds)；
setInterval(function, milliseconds, param1, param2, ...)； 

<template>
  <div>
    <h1>{{value}}</h1>
    <el-button type="primary" @click="start">开始</el-button>
    <el-button type="danger" @click="over">结束</el-button>
  </div>
</template>
<script>
export default {
  data() {
    return {
      timer: "",
      value: 0,
    };
  },
  methods: {
    start(){
      this.timer = setInterval(this.valChange, 2000); // 注意: 第一个参数为方法名的时候不要加括号;
    },
    valChange() {
      this.value++;
      console.log(this.value);
    },
    over(){
      clearInterval(this.timer);
    }
  },
  mounted() {},
  beforeDestroy() {
    clearInterval(this.timer);
  },
};
</script>

setTimeout(code, milliseconds, param1, param2, ...)
setTimeout(function, milliseconds, param1, param2, ...)

let timer = setTimeout(() => {
  //需要定时执行的代码
  console.debug("Hello World");
  }, 2000)