luxon - 使用 luxon 库显示相对于给定时间的时间

Question

luxon 是否支持显示相对于给定时间的功能？

Moment 具有“日历时间”功能：

https://momentjs.com/docs/#/displaying/calendar-time/

moment().calendar(null, {
   sameDay: '[Today]',
   nextDay: '[Tomorrow]',
   nextWeek: 'dddd',
   lastDay: '[Yesterday]',
   lastWeek: '[Last] dddd',
   sameElse: 'DD/MM/YYYY'
});

我可以使用 luxon 实现相同的目标吗？

Answer 1

从版本1.9.0您可以使用toRelativeCalendar：

返回此日期相对于今天的字符串表示形式，例如“昨天”或“下个月”平台支持Intl.RelativeDateFormat。

const DateTime = luxon.DateTime;

const now = DateTime.local();
// Some test values
[ now,
  now.plus({days: 1}),
  now.plus({days: 4}),
  now.minus({days: 1}),
  now.minus({days: 4}),
  now.minus({days: 20}),
].forEach((k) => {
  console.log( k.toRelativeCalendar() );
});

<script src="https://cdn.jsdelivr.net/npm/luxon@1.10.0/build/global/luxon.js"></script>

---

在 version 之前， Luxon1.9.0中没有等价物。calendar()

在 DateTime 方法等效 => 输出 =>人性化部分中说明的For Moment 用户手册页：

Luxon 不支持这些，并且在相对时间格式提案登陆浏览器之前不会支持。

Operation       | Moment     | Luxon
---------------------------------------------------------------------------------------
"Calendar time" | calendar() | None (before 1.9.0) / toRelativeCalendar() (after 1.9.0)

如果需要，您可以自己编写一些东西，这里有一个自定义函数示例，它具有类似的 moment's 输出calendar()：

const DateTime = luxon.DateTime;

function getCalendarFormat(myDateTime, now) {
  var diff = myDateTime.diff(now.startOf("day"), 'days').as('days');
  return diff < -6 ? 'sameElse' :
    diff < -1 ? 'lastWeek' :
    diff < 0 ? 'lastDay' :
    diff < 1 ? 'sameDay' :
    diff < 2 ? 'nextDay' :
    diff < 7 ? 'nextWeek' : 'sameElse';
}

function myCalendar(dt1, dt2, obj){
  const format = getCalendarFormat(dt1, dt2) || 'sameElse';
  return dt1.toFormat(obj[format]);
}

const now = DateTime.local();
const fmtObj = {
   sameDay: "'Today'",
   nextDay: "'Tomorrow'",
   nextWeek: 'EEEE',
   lastDay: "'Yesterday'",
   lastWeek: "'Last' EEEE",
   sameElse: 'dd/MM/yyyy'
};

// Some test values
[ now,
  now.plus({days: 1}),
  now.plus({days: 4}),
  now.minus({days: 1}),
  now.minus({days: 4}),
  now.minus({days: 20}),
].forEach((k) => {
  console.log( myCalendar(now, k, fmtObj) );
});

<script src="https://cdn.jsdelivr.net/npm/luxon@1.8.2/build/global/luxon.js"></script>

这段代码大致灵感来自 moment code，它肯定可以改进。