优化下面代码getCarbonTotalNumber() { let _this = this let carType = {carType: this.vType == 'noType' ? "" : this.vType} getCarbonDayNumber(carType).then(response => { _this.count.end = response.data }); setTimeout(function () { _this.count.start = _this.count.end }, 100) }

这段代码可以进行一些优化：

1. 可以使用箭头函数来避免使用_this = this：

getCarbonTotalNumber() {
  let carType = {carType: this.vType == 'noType' ? "" : this.vType}
  getCarbonDayNumber(carType).then(response => {
    this.count.end = response.data
  });
  setTimeout(() => {
    this.count.start = this.count.end
  }, 100)
}

2. 可以使用async/await来避免使用回调函数：

async getCarbonTotalNumber() {
  let carType = {carType: this.vType == 'noType' ? "" : this.vType}
  let response = await getCarbonDayNumber(carType)
  this.count.end = response.data
  setTimeout(() => {
    this.count.start = this.count.end
  }, 100)
}

3. 可以使用Promise.all来同时调用多个接口：

async getCarbonTotalNumber() {
  let carType = {carType: this.vType == 'noType' ? "" : this.vType}
  let [response1, response2] = await Promise.all([
    getCarbonDayNumber(carType),
    getCarbonWeekNumber(carType)
  ])
  this.count.end = response1.data + response2.data
  setTimeout(() => {
    this.count.start = this.count.end
  }, 100)
}

注意：这些代码都是基于假设你已经正确地导入了相关的函数和变量。