Lodash groupBy 与时刻答案

【问题标题】：Lodash groupBy with momentLodash groupBy 与时刻
【发布时间】：2017-11-15 08:06:43
【问题描述】：

我正在尝试按今天、本周、本月和前几个月对一组日期进行分组。但是，在我达到这一点之前，我什至很难按月进行基本分组。

const data = [{
 campaign: "Charles",
 company_ID: "1",
 coreURL: "http://www.test77.com",
 createdAt: "2017-11-06T20:45:56.931Z",
 owner: "K7xTxu7PRDCuhFZRC",
 updatedAt: "2017-09-06T20:45:56.931Z",
 _id: "6gsb42PSSJt7PgsDG"
}, {
 campaign: "Charles",
 company_ID: "1",
 coreURL: "http://www.test66,com",
 createdAt: "2017-11-06T20:46:27.744Z",
 owner: "K7xTxu7PRDCuhFZRC",
 updatedAt: "2017-10-06T20:46:27.744Z",
 _id: "Md4wCnEsrQrWApnLS"
}, {
 campaign: "Gary",
 company_ID: "1",
 coreURL: "http://www.test55,com",
 createdAt: "2017-11-06T20:46:27.744Z",
 owner: "K7xTxu7PRDCuhFZRC",
 updatedAt: "2017-07-06T20:46:27.744Z",
 _id: "5p44uiwRgqp35YXRf"
}
];

const grouper = 'updatedAt';

let groupedData = _
  .chain(data)
  .groupBy(datum => moment(datum.grouper).format("MM"))

编辑：但是这似乎只按“11”（今天的月份）分组

任何帮助将不胜感激

【问题讨论】：

标签： javascript momentjs lodash

【解决方案1】：

datum.grouper 是 undefined，所以 moment(datum.grouper) 返回当前日期。

您应该改用datum[grouper] 或类似_.property('updatedAt') 的东西。

关于如何将日期划分为今天、本周、本月和其他月份的问题，请尝试以下操作：

const data = [{
  campaign: "Charles",
  company_ID: "1",
  coreURL: "http://www.test77.com",
  createdAt: "2017-11-06T20:45:56.931Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-09-06T20:45:56.931Z",
  _id: "6gsb42PSSJt7PgsDG"
}, {
  campaign: "Charles",
  company_ID: "1",
  coreURL: "http://www.test66,com",
  createdAt: "2017-11-06T20:46:27.744Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-10-06T20:46:27.744Z",
  _id: "Md4wCnEsrQrWApnLS"
}, {
  campaign: "Gary",
  company_ID: "1",
  coreURL: "http://www.test55,com",
  createdAt: "2017-11-06T20:46:27.744Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-07-06T20:46:27.744Z",
  _id: "5p44uiwRgqp35YXRf"
}, {
  campaign: "Fred",
  company_ID: "1",
  coreURL: "http://www.test55,com",
  createdAt: "2017-11-06T20:46:27.744Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-11-15T03:46:27.744Z",
  _id: "5p44uiwRgqp35YXRf"
}, {
  campaign: "Fred",
  company_ID: "1",
  coreURL: "http://www.test55,com",
  createdAt: "2017-11-06T20:46:27.744Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-11-03T20:46:27.744Z",
  _id: "5p44uiwRgqp35YXRf"
}, {
  campaign: "Fred",
  company_ID: "1",
  coreURL: "http://www.test55,com",
  createdAt: "2017-11-06T20:46:27.744Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-11-13T20:46:27.744Z",
  _id: "5p44uiwRgqp35YXRf"
}, {
  campaign: "Fred",
  company_ID: "1",
  coreURL: "http://www.test55,com",
  createdAt: "2017-11-06T20:46:27.744Z",
  owner: "K7xTxu7PRDCuhFZRC",
  updatedAt: "2017-11-09T20:46:27.744Z",
  _id: "5p44uiwRgqp35YXRf"
}];

const groupProp = _.property('updatedAt');

let determineGroup = value => {
  // remove '2017-11-15' to actually use current date 
  const now = moment('2017-11-15T10:00:03Z').startOf('day');

  if (value.isSame(now, 'day')) {
    return 'today';
  }
  if (value.isAfter(now.clone().subtract(7, 'days').startOf('day'))) {
    return 'this week';
  }
  if (value.isSame(now, 'month')) {
    return 'this month';
  }
  return value.format('MM');
};

let groupedData = _
  .chain(data)
  .groupBy(datum => determineGroup(moment(groupProp(datum))))
  .value()

console.log(groupedData);

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.19.2/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>

【讨论】：

非常感谢。您对如何有条件地分组有任何想法（即今天，本周，本月）:-)
@NickWild “本周”会包括“今天”项目还是排除它们？您会将“本周”定义为“过去 7 天”还是“自一周中某一天（星期日/星期一）以来的时间”？关于“本月”的类似问题。
本周将排除今天，可能是过去 7 天而不是日历周，但本月将是实际月份（但不包括过去 7 天），然后其他历史月份将只是常规日历个月。谢谢！
@NickWild 好的，请查看我的更新答案。我使用了一个函数将日期分类到您指定的组中。
那是完美的。感谢您花时间编写此代码

【解决方案2】：

let groupedData = _
.chain(data)
.groupBy(record => moment(record.updatedAt).format("MM"))
.value();

【讨论】：

【解决方案3】：

如果您只需要当前月、日、年，也许您可以使用过滤器。

const today = _.filter(data, d => moment(d.updatedAt).isSame(moment(), 'day'));
console.log(today);

const thisWeek = _.filter(data, d => moment(d.updatedAt).isSame(moment(), 'week'));
console.log(thisWeek);

const thisMonth = _.filter(data, d => moment(d.updatedAt).isSame(moment(), 'month'));
console.log(thisMonth);

或 groupBy 如果您需要所有月份（所有年份）

const byMonth = _.groupBy(data, d => moment(d.updatedAt).month());
console.log(byMonth);

https://jsbin.com/xidido/edit?js,console

【讨论】：