javascript - 打印数组内某些对象日期范围内包含的所有日期的最佳方法是什么？

Question

如果我有一个像这样的对象数组:

{
    "workPeriods": [
        {
            "user_id": "9345bf",
            "startDate": "2018-02-05T05:00:00.000Z",
            "endDate": "2018-02-09T05:00:00.000Z"
        },
        {
            "user_id": "80c3a9",
            "startDate": "2018-02-12T05:00:00.000Z",
            "endDate": "2018-02-16T05:00:00.000Z"
        },
        {
            "user_id": "35jh87",
            "startDate": "2018-02-19T05:00:00.000Z",
            "endDate": "2018-02-23T05:00:00.000Z"
        }
    ]
}

打印每个对象日期范围内包含的所有日期的最佳方式是什么？
这需要使用 Moment jS 来完成

结果应该是这样的:

'Work days: 02/05, 02/06, 02/07, 02/08, 02/09,   02/12, 02/13, 02/14, 02/15, 02/16,   02/19, 02/20, 02/21, 02/22, 02/23'

有什么建议吗？ 谢谢!

Answer 1

我不确定解决问题的“最佳”方法到底是什么意思，因为您没有指定评估解决方案的标准。看到functional-programming其他标签让我编写一些我认为相关的代码。

在下面的代码中(您可以test out here):

• 首先 map() 将每个工作周期转换为该周期中的一组天数。这将产生“数组的数组”。
• reduce() 将数组扁平化为单个数组。
• 然后，map() 将每个 moment.js Moment 对象格式化为其字符串表示形式。
• 最后，join(' ') 将其转换为单个字符串，其中所有日期均以空格分隔。

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如果您使用 ES6 或 TypeScript 编写:

const sourceObject = {
  "workPeriods": [
    {"user_id":"9345bf", "startDate":"2018-02-05T05:00:00.000Z", "endDate":"2018-02-09T05:00:00.000Z"},
    {"user_id":"80c3a9", "startDate":"2018-02-12T05:00:00.000Z", "endDate":"2018-02-16T05:00:00.000Z"},
    {"user_id":"35jh87", "startDate":"2018-02-19T05:00:00.000Z", "endDate":"2018-02-23T05:00:00.000Z"}
  ]
};

const userFriendlyWorkPeriodsDayList = sourceObject
  .workPeriods
  .map(workPeriod => {
    const allDaysInRange = [];
    const currentDate = moment(workPeriod.startDate);
    const endDate = moment(workPeriod.endDate);

    while (currentDate.isBefore(endDate)) {
      allDaysInRange.push(currentDate.clone());
      currentDate.add(1, 'days');
    }

    return allDaysInRange;
  })
  .reduce((accumulator, current) => (accumulator.push(...current), accumulator), [])
  .map(date => date.format('MM/DD'))
  .join(' ');

const result = `Work days: ${userFriendlyWorkPeriodsDayList}`;

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在旧版本的 JavaScript 中重写的相同代码需要使用 function 关键字而不是 =>。它们还可能缺乏扩展运算符支持 (.push(...arrayOfValuesBeingPushed))。

const sourceObject = {
  "workPeriods": [
    {"user_id":"9345bf", "startDate":"2018-02-05T05:00:00.000Z", "endDate":"2018-02-09T05:00:00.000Z"},
    {"user_id":"80c3a9", "startDate":"2018-02-12T05:00:00.000Z", "endDate":"2018-02-16T05:00:00.000Z"},
    {"user_id":"35jh87", "startDate":"2018-02-19T05:00:00.000Z", "endDate":"2018-02-23T05:00:00.000Z"}
  ]
};

const userFriendlyWorkPeriodsDayList = sourceObject
  .workPeriods
  .map(function (workPeriod) {
    const allDaysInRange = [];
    const currentDate = moment(workPeriod.startDate);
    const endDate = moment(workPeriod.endDate);

    while (currentDate.isBefore(endDate)) {
      allDaysInRange.push(currentDate.clone());
      currentDate.add(1, 'days');
    }

    return allDaysInRange;
  })
  .reduce(function (accumulator, current) { accumulator.push(...current); return accumulator; }, [])
  .map(function (date) { return date.format('MM/DD'); })
  .join(' ');

const result = `Work days: ${userFriendlyWorkPeriodsDayList}`;

console.log(result)

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