HTML5 Intl API每周的第一天

Question

有没有办法从HTML5国际化API获取一周的第一天(大多数国家的周日或周一)？

规范可以在这里找到.如果它没有以某种方式披露我会感到惊讶,但我似乎无法找到它.

Answer 1

Intl还没有访问此类日历信息的 API。它可能会在未来增加对这样做的支持，但现在你不走运。

Answer 2

用于检索此信息的官方普通 API 是Locale.prototype.getWeekInfo()，或者当前更受支持的Locale.prototype.weekInfo（Firefox 也不支持！）：

小提示：Firefox 也不支持！

// New API, currently only in Deno, Bun & Safari Technology Preview (2023-10)
new Intl.Locale('en-US').getWeekInfo()

// "Old" API, available in Chrome, Edge, Opera, Node & other Chromium-based browsers
new Intl.Locale('en-US').weekInfo

它将返回一个像这样的对象：

{
    firstDay: 7,      // First day of the week is Sunday
    minimalDays: 1,   // First calendar week of the year must have at least 1 weekday
    weekend: [6, 7]   // Weekend is Saturday and Sunday
}

其他文化的示例：( new Intl.Locale('<locale>').weekInfo)

德国de-DE：

{
    firstDay: 1,      // First day of the week is Monday
    minimalDays: 4,   // First calendar week of the year has at least 4 weekdays
    weekend: [6, 7]   // Weekend is Saturday and Sunday
}

埃及ar-EG:

{
    firstDay: 6,      // First day of the week is Saturday
    minimalDays: 1,   // First calendar week of the year has at least 1 weekday
    weekend: [5, 6]   // Weekend is Friday and Saturday
}

乌干达sw-UG:

{
    firstDay: 1,      // First day of the week is Monday
    minimalDays: 1,   // First calendar week of the year has at least 1 weekday
    weekend: [7]      // Weekend is Sunday only
}

文莱ms-BN：

{
    firstDay: 7,      // First day of the week is Sunday
    minimalDays: 1,   // First calendar week of the year has at least 1 weekday
    weekend: [5, 7]   // Weekend is Friday and Sunday
}

Polyfilling 这是可能的，但我推荐优秀的date-fns库，直到TemporalAPI 到达大多数浏览器，它具有适用于当前 93 个语言环境的类似数据（没有周末信息）：

import { enUS, deAT, ar, hi } from 'date-fns/locale'

enUS.options.weekStartsOn          // 0 <- careful, 0 = Sunday
enUS.options.firstWeekContainsDate // 1

deAT.options.weekStartsOn          // 1
deAT.options.firstWeekContainsDate // 4

// Arabic
ar.options.weekStartsOn            // 6
ar.options.firstWeekContainsDate   // 1

// Hindi
hi.options.weekStartsOn            // 0
hi.options.firstWeekContainsDate   // 4

小注意事项 - 规范已从属性更改为函数，因为所有浏览器/运行时都实现weekInfo为 getter，它总是返回一个新对象，并导致这种不直观的行为：

const swedish = new Intl.Locale('sv');
swedish.weekInfo === swedish.weekInfo  // false