javascript - 如何使用 moment.js 按本周和上周记录对数据进行分组

Question

我有一个包含日期属性的对象数组。我想按本周的记录和上周的记录对其进行分组。使用 javascript 和 moment.js 实现此目的的最佳方法是什么？以下是数据集的结构。

const obj = [{
   first_name: "Peter",
   last_name: "Hansen",
   date: "2018-01-01"
},
{  first_name: "Jonas",
   last_name:"Da Vinci",
   date: "2018-01-02"
},
{  first_name: "Ohmel",
   last_name: "Reynolds",
   date: "2018-01-03"
},
{  first_name: "Raisa",
   last_name: "Johnson",
   date: "2017-12-25"

},
{
   first_name: "Karen",
   last_name: "Anderson",
   date: "2017-12-26"
},
{
   first_name: "Kristina",
   last_name: "Alvaro",
   date: "2017-12-27"
}]

预期输出:

本周

• 彼得·汉森
• 乔纳斯·达芬奇
• 欧梅尔·雷诺兹

上周

• 赖莎·约翰逊
• 凯伦·安德森
• 克里斯蒂娜·安德森

Answer 1

您可以使用 array#reduce 按周对数组进行分组。

const arr = [{ first_name: "Peter", last_name: "Hansen", date: "2018-01-01" }, { first_name: "Jonas", last_name:"Da Vinci", date: "2018-01-02" }, { first_name: "Ohmel", last_name: "Reynolds", date: "2018-01-03" }, { first_name: "Raisa", last_name: "Johnson", date: "2017-12-25"}, { first_name: "Karen", last_name: "Anderson", date: "2017-12-26" }, { first_name: "Kristina", last_name: "Alvaro", date: "2017-12-27" }];
var sortedByWeek = arr.reduce((res, {date, first_name, last_name}) => {
  var startOfWeek = moment(date, 'YYYY-MM-DD').startOf('week').add(1,'days').format('YYYY-MM-DD');
  res[startOfWeek] = res[startOfWeek] || [];
  res[startOfWeek].push(first_name + ' ' + last_name);
  return res;
},{});

console.log(sortedByWeek);

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