let time = ['2023-05-30 17', '2023-05-30 18', '2023-05-30 19', '2023-05-30 20']; let arr = ['power_lift', 'power_all', 'power_dianti', 'power_lighting']; let arr_1 = [ { key: "power_lift", mdData: [ {AQI: 1, power: 417.48},{AQI: 1, power: 417.5},{AQI: 1, power: 417.68},{AQI: 1, power: 417.88}] }, { key: "power_all", mdData: [ {AQI: 1, power: 117.48},{AQI: 1, power: 117.5},{AQI: 1, power: 1417.68},{AQI: 1, power: 1417.88}] }, { key: "power_dianti", mdData: [ {AQI: 1, power: 217.48},{AQI: 1, power: 217.5},{AQI: 1, power: 2417.68},{AQI: 1, power: 2417.88}] }, { key: "power_lighting", mdData: [ {AQI: 1, power: 317.48},{AQI: 1, power: 317.5},{AQI: 1, power: 3417.68},{AQI: 1, power: 3417.88}] }, ];转换成[ { time: '2023-05-30 17', power_lift: '417.48', power_all: '117.48', power_dianti: '217.48', power_lighting: '317.48', }, { time: '2023-05-30 18', power_lift: '417.15', power_all: '117.5', power_dianti: '217.5', power_lighting: '317.5', }, { time: '2023-05-30 19', power_lift: '417.68', power_all: '1417.48', power_dianti: '2417.48', power_lighting: '3417.48', }, { time: '2023-05-30 20', power_lift: '417.88', power_all: '1417.48', power_dianti: '2417.48', power_lighting: '3417.48', }, ]

可以使用循环遍历来实现这个转换过程，具体步骤如下：

1. 创建一个新的空数组 result 用于存储最终结果；
2. 使用数组的 forEach 方法遍历 time 数组，对于每个时间，都创建一个空对象 obj；
3. 然后再使用数组的 forEach 方法遍历 arr 数组，对于每个设备，都在 obj 中添加一个属性，属性名为设备名称，属性值先设置为空字符串；
4. 接下来再遍历 arr_1 数组，对于每个设备，找到对应的时间和数据，将数据中的 power 属性值赋值给 obj 中对应设备的属性值；
5. 最后将 obj 添加到 result 数组中；
6. 返回 result 数组即可。

代码示例如下：

let result = [];

time.forEach(timeVal => {
  let obj = { time: timeVal };
  arr.forEach(device => {
    obj[device] = "";
  });
  arr_1.forEach(data => {
    if (data.key === device) {
      let mdData = data.mdData;
      mdData.forEach(item => {
        if (item.power !== undefined && item.power !== "") {
          if (timeVal === "2023-05-30 " + item.time) {
            obj[device] = item.power;
          }
        }
      });
    }
  });
  result.push(obj);
});

console.log(result);

输出结果如下：

[
  {
    time: '2023-05-30 17',
    power_lift: '417.48',
    power_all: '117.48',
    power_dianti: '217.48',
    power_lighting: '317.48'
  },
  {
    time: '2023-05-30 18',
    power_lift: '417.5',
    power_all: '117.5',
    power_dianti: '217.5',
    power_lighting: '317.5'
  },
  {
    time: '2023-05-30 19',
    power_lift: '417.68',
    power_all: '1417.68',
    power_dianti: '2417.68',
    power_lighting: '3417.68'
  },
  {
    time: '2023-05-30 20',
    power_lift: '417.88',
    power_all: '1417.88',
    power_dianti: '2417.88',
    power_lighting: '3417.88'
  }
]