javascript - 如何循环遍历对象数组，将键推送到另一个数组

Question

我有以下数组，我想循环遍历它并将键值推送到另一个声明的数组。然后，循环遍历数组并将键的字段和值推送到另一个数组。

timeframe = [];

timeframeValueKeyUSD = [];

timeframeValueKeyCAD = [];

array = [
       {
      "2012-05-01":{
        "USD": 1.322891,
        "AUD": 1.278047,
        "CAD": 1.302303
      },
      "2012-05-02": {
        "USD": 1.315066,
        "AUD": 1.274202,
        "CAD": 1.299083
      },
      "2012-05-03": {
        "USD": 1.314491,
        "AUD": 1.280135,
        "CAD": 1.296868
      }
  }
]

我想得到这样的数组:

timeframe = ['2012-05-01', '2012-05-02', '2012-05-03'];

timeframeValueKeyUSD = [1.315066, 1.315066, 1.314491];

timeframeValueKeyCAD = [1.302303, 1.299083, 1.296868];

Answer 1

您可以先获取日期，然后根据日期映射值。

function getKeys(o) {
    return Object.keys(o);
}

function getValueBy(object, groups, key) {
    return groups.map(k => object[k][key]);
}

var array = [{ "2012-05-01":{ USD: 1.322891, AUD: 1.278047, CAD: 1.302303 }, "2012-05-02": { USD: 1.315066, AUD: 1.274202, CAD: 1.299083 }, "2012-05-03": { USD: 1.314491, AUD: 1.280135, CAD: 1.296868 } }],
    timeframe = getKeys(array[0]);
    timeframeValueKeyUSD = getValueBy(array[0], timeframe, 'USD'),
    timeframeValueKeyCAD = getValueBy(array[0], timeframe, 'CAD');

console.log(timeframe);
console.log(timeframeValueKeyUSD);
console.log(timeframeValueKeyCAD);

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