Infinite Unixtime

GitHub npm

能够精确处理从公元前到无限未来所有时间范围的时区与日期处理函数库。所有对象保持不可变，杜绝过去日期上的地方平均时 (LMT) 误差；支持各类格式解析与时区功能，在 npm 与原生打包环境中都能灵活使用。

1970-01-01 (Thu) 00:00:00.000 Z

unixtime · 秒

unixtime · 毫秒

年

月

日

时

分

秒

毫秒

1970-01

Sun

Mon

Tue

Wed

Thu

Fri

Sat

时00

分00

秒00

毫秒000

TZUTC±00:00

ISO 8601

1970-01-01T00:00:00.000Z

API 文档

安装

bash

npm install infinite-unixtime
pnpm add infinite-unixtime
yarn add infinite-unixtime

javascript

import { Unixtime } from 'infinite-unixtime';

时区偏移

不使用时区数据库。所有 API 接收以分钟为单位的固定偏移，符号与 Date.prototype.getTimezoneOffset 一致。因此地方平均时不会混入旧日期。

javascript

// UTC+09:00 -> -540, UTC -> 0, UTC-03:30 -> 210
const KST = -540;
const UTC = 0;

// The browser's own offset, same sign convention.
const local = new Date().getTimezoneOffset();

// Every API takes the offset last; omitting it uses the browser's.
Unixtime.fromUtc(2026, 3, 31, 5, 30).format('yyyy-MM-dd HH:mm', KST);
//=> '2026-03-31 14:30'

创建

javascript

Unixtime.now();
Unixtime.fromDate(new Date());

Unixtime.fromMillis(1774935005123n).toIsoStringUtc();
//=> '2026-03-31T05:30:05.123Z'

Unixtime.fromSeconds(1774935005).toIsoStringUtc();
//=> '2026-03-31T05:30:05.000Z'

// year, month, day, hour, minute, second, millisecond, timezoneOffset
Unixtime.from(2026, 3, 31, 14, 30, 0, 0, -540).toIsoStringUtc();
//=> '2026-03-31T05:30:00.000Z'

Unixtime.fromUtc(2026, 3, 31, 14, 30).toIsoStringUtc();
//=> '2026-03-31T14:30:00.000Z'

javascript

// No year limit — the value is one bigint of milliseconds.
Unixtime.fromUtc(23948923423421773421234n, 1, 31).timestamp;
//=> 755755026924596579546592556800000n

Unixtime.fromUtc(-2000, 2, 29).toIsoStringUtc();
//=> '-2000-02-29T00:00:00.000Z'

// A date that does not exist throws.
Unixtime.fromUtc(2026, 2, 29);
//=> Error: Unixtime: Invalid Date: 2026-2-29 0:0:0.0

解析

解析遵循与格式化相同的格式。格式不匹配时不会猜测，而是抛出异常。

javascript

Unixtime.parseUtc('2026-03-31T14:30:00.000Z', 'yyyy-MM-ddTHH:mm:ss.SSSXXX').toIsoStringUtc();
//=> '2026-03-31T14:30:00.000Z'

Unixtime.parseUtc('20260331143000000', 'yyyyMMddHHmmssSSS').toIsoStringUtc();
//=> '2026-03-31T14:30:00.000Z'

Unixtime.parseUtc('2026-03-31 PM 09:30', 'yyyy-MM-dd a hh:mm').toIsoStringUtc();
//=> '2026-03-31T21:30:00.000Z'

// An offset in the text wins over the argument.
Unixtime.parse('2026-03-31T14:30:00.000+09:00', 'yyyy-MM-ddTHH:mm:ss.SSSXXX', 0).toIsoStringUtc();
//=> '2026-03-31T05:30:00.000Z'

Unixtime.parseUtc('2026-03-31 00:00 +0900', 'yyyy-MM-dd HH:mm XXX').toIsoStringUtc();
//=> '2026-03-30T15:00:00.000Z'

// Missing fields default to 1970-01-01 00:00:00.000
Unixtime.parseUtc('12:34', 'HH:mm').timestamp;
//=> 45240000n

Unixtime

默认返回 bigint，使用 $ 则返回 number。

javascript

// 2026-03-31 14:30:05.123 +09:00
const u = Unixtime.fromUtc(2026, 3, 31, 5, 30, 5, 123);

u.timestamp;    //=> 1774935005123n   bigint, milliseconds
u.time;         //=> 1774935005n      bigint, seconds
u.$timestamp;   //=> 1774935005123    number, milliseconds
u.$time;        //=> 1774935005       number, seconds

日期时间、时间

需要多个字段时，用它而不是逐个 getter。进位只计算一次，负时间戳下取值也不会错位。

javascript

const u = Unixtime.fromUtc(2026, 3, 31, 5, 30, 5, 123);

u.toDateTimeDetail(-540);
//=> { leapYear: false, year: 2026n, month: 3, day: 31, week: 2,
//     hours: 14, minutes: 30, seconds: 5, milliseconds: 123,
//     timezoneOffset: -540 }

u.toTimeDetail(-540);
//=> { hours: 14, minutes: 30, seconds: 5, milliseconds: 123,
//     timezoneOffset: -540 }

格式化

javascript

const u = Unixtime.fromUtc(2026, 3, 31, 5, 30, 5, 123);

u.format('yyyy-MM-dd (E) HH:mm:ss.SSS XXX', -540);
//=> '2026-03-31 (Tue) 14:30:05.123 +09:00'

u.formatUtc('yyyy-MM-dd HH:mm');
//=> '2026-03-31 05:30'

u.toString(-540);
//=> '2026-03-31 (Tue) PM 02:30 05.123 +09:00'

u.toStringUtc();
//=> '2026-03-31 (Tue) AM 05:30 05.123 Z'

u.toIsoString(-540);
//=> '2026-03-31T14:30:05.123+09:00'

u.toIsoStringUtc();
//=> '2026-03-31T05:30:05.123Z'

txt

yyyy  year, no padding limit      yy   2-digit year
MM    month 01-12                dd   day 01-31
HH    hour 00-23                 hh   hour 01-12
a     AM / PM                    mm   minute 00-59
ss    second 00-59               SSS  millisecond 000-999
E     Tue        EE  Tuesday     e    day of week 0-6
XXX   +09:00 / Z                 '..' literal text

相对时间

toRelative 返回相对于当前时间的相对时间。

javascript

const base = Unixtime.fromUtc(2026, 3, 31, 12, 0);
const u = base.plusMinutes(-90);

u.toRelative({ base, locale: 'en' });   //=> '1 hour ago'
u.toRelative({ base, locale: 'ko' });   //=> '1시간 전'

u.toRelativeDetail({ base });
//=> { value: -1, unit: 'hour', millis: -5400000n }

// Past the limit it returns null instead of a stale phrase.
base.plusDays(-31).toRelativeDetail({ base });
//=> null

javascript

u.toRelative({
  base: Unixtime.now(),          // what to measure against
  limit: { days: 30 },           // false to disable
  units: ['day', 'hour'],        // day | hour | minute | second
  future: 'keep',                // 'now' clamps the future to 0
  locale: 'ko',
  numeric: 'auto',               // 'always' | 'auto'
  style: 'long',                 // 'long' | 'short' | 'narrow'
});

日期

所有取值都以偏移作为最后一个参数，省略时使用浏览器时区。

javascript

// 2026-03-31 14:30:05.123 +09:00
const u = Unixtime.fromUtc(2026, 3, 31, 5, 30, 5, 123);

u.getYear(-540);            //=> 2026n
u.getYearNumber(-540);      //=> 2026
u.getMonth(-540);           //=> 3
u.getDay(-540);             //=> 31
u.getLastDayOfMonth(-540);  //=> 31
u.getDayOfYear(-540);       //=> 90
u.isLeapYear(-540);         //=> false

星期与周次

普通周次以周日为起始、每周至少 1 天，ISO 周次以周一为起始、每周至少 4 天。

javascript

const u = Unixtime.fromUtc(2026, 3, 31, 5, 30, 5, 123);

u.getWeek(-540);        //=> 2          0 = Sunday
u.getWeekShort(-540);   //=> 'Tue'
u.getWeekLong(-540);    //=> 'Tuesday'

u.getWeekOfMonth(-540);         //=> 5
u.getLastWeekOfMonth(-540);     //=> 5
u.getWeekOfYear(-540);          //=> 14
u.getLastWeekOfYear(-540);      //=> 53

u.getIsoWeekOfMonth(-540);      //=> 5
u.getLastIsoWeekOfMonth(-540);  //=> 5
u.getIsoWeekOfYear(-540);       //=> 14
u.getLastIsoWeekOfYear(-540);   //=> 53

时间

javascript

const u = Unixtime.fromUtc(2026, 3, 31, 5, 30, 5, 123);

u.getHours(-540);         //=> 14
u.getHours12(-540);       //=> 2
u.getAmPm(-540);          //=> 'PM'
u.getMinutes(-540);       //=> 30
u.getSeconds(-540);       //=> 5
u.getMilliseconds(-540);  //=> 123

移动

实例不可变，每次调用都会产生新值。按月、按年移动会保留日期，若该日不存在则调整为当月最后一天。

javascript

const u = Unixtime.fromUtc(2026, 1, 31);

u.plusMillis(500);
u.plusSeconds(-30);
u.plusMinutes(15);
u.plusHours(-8);

u.plusDays(7).toIsoStringUtc();
//=> '2026-02-07T00:00:00.000Z'

// The day is kept, then clamped to the last of the month.
u.plusMonth(1, 0).toIsoStringUtc();
//=> '2026-02-28T00:00:00.000Z'

Unixtime.fromUtc(2024, 1, 31).plusMonth(1, 0).toIsoStringUtc();
//=> '2024-02-29T00:00:00.000Z'

u.plusYear(-1, 0).toIsoStringUtc();
//=> '2025-01-31T00:00:00.000Z'

比较

比较函数接受工厂函数能接受的任何值，因此无需转换 Date 或数字。

javascript

const a = Unixtime.fromUtc(2026, 3, 31);
const b = Unixtime.fromUtc(2026, 4, 1);

a.before(b);     //=> true
a.beforeEq(b);   //=> true
a.after(b);      //=> false
a.afterEq(b);    //=> false

a.between(Unixtime.fromUtc(2026, 1, 1), b);
//=> true

// Accepts Unixtime | number | bigint | string | Date.
a.before(new Date());

// Second argument compares by seconds instead of milliseconds.
a.before(b, true);

类型

typescript

type TimeInput = Unixtime | number | bigint | string | Date;
type RelativeUnit = 'day' | 'hour' | 'minute' | 'second';

type DateTimeDetail = {
  readonly leapYear: boolean;
  readonly year: bigint;
  readonly month: number;
  readonly day: number;
  readonly hours: number;
  readonly minutes: number;
  readonly seconds: number;
  readonly milliseconds: number;
  readonly week: number;
  readonly timezoneOffset: number;
};

type RelativeDetail = {
  readonly value: number;
  readonly unit: RelativeUnit;
  readonly millis: bigint;
};