轮循

// 轮询功能
getCircle() {
  const { fetch } = this
  this.timer = window.setInterval(() => {
    setTimeout(() => {
      fetch()
    }, 0)
  }, 2000)
}

销毁和开始

beforeRouteEnter(to, from, next) {
  next(v => v.getCircle())
},
beforeRouteLeave(to, from, next) {
  window.clearInterval(this.timer)
  next()
},

文件数据上传

async handleSave(){
  const formData = new FormData()
  formData.set('file', this.file)
  const res = await updateImg(formData)
  if(res.status === 200){
    console.log(res);
    console.log('保存')
  }