Lodash groupBy 带有 React 的胖箭头函数

Question

从Lodash groupBy with moment 开始，通过使用胖箭头函数和时刻等日期对数组进行分组，例如今天、本周、月份等，我现在尝试启用 if then else（或三元），仅在 if排序参数（从 state 传入）实际上是一个日期。

这就是我目前所拥有的......

     let groupby = datum => {
        if (this.state.sortGroup ='updatedAt') {
          return determineGroup(moment(groupProp(datum)));
        } else {
          this.state.sortGroup
        }
      }

      //console log point 1 -  shows state change

      groupedData = _
      .chain(this.props.records)
      .groupBy(groupby)
      .map(function(val, key) {
          return {
              group: key,
              records: val
          };
      })
      .value()

      //console log point 2 -  no state change

它完美地按分组的 createdAt 排序，但是当我将 if then else 功能放入其中时，它不会按任何其他道具排序。同样有趣的是，在日志点 2 中，它没有显示状态变化。

这是我做错了什么，会影响 if then else 函数中的状态或糟糕的代码吗？

Answer 1

我假设sortGroup 指的是数据上的属性名称，在这种情况下，我认为您需要更多类似的东西：

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');
};

this.state = {
  sortGroup: 'updatedAt'
};

let groupby = datum => {
  const groupValue = datum[this.state.sortGroup];

  if (this.state.sortGroup === 'updatedAt') {
    return determineGroup(moment(groupValue));
  } else {
    return groupValue;
  }
}

let groupedData = _
  .chain(data)
  .groupBy(groupby)
  .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>