重新格式化日期字符串是相当简单的，例如。

var s = ' 2014年5月11日'; 函数reformatDate(s) { 函数z(n){return ('0' + n).slice(-2)} var月=[‘简’,2月,3月,4月,“可能”,“君”, 7月,8月,9月,10月,11月,12月的]; var b = s.split(/\W+/); 返回b[3] + '-' + z (months.indexOf (b [1] .substr .toLowerCase (0, 3) ())) + '-' + z (b [2]); ｝ console.log (reformatDate (s));

最短的

.toJSON().slice(0,10);

var d =新的日期(' 2014年5月11日' +' UTC');//解析为UTC let str = d.toJSON().slice(0,10);//显示为UTC console.log (str);

所有给出的答案都很棒，对我帮助很大。在我的情况下，我希望以yyyy mm dd格式和date-1获取当前日期。以下是对我有效的方法。

var endDate = new Date().toISOString().slice(0, 10); // To get the Current Date in YYYY MM DD Format

var newstartDate = new Date();
newstartDate.setDate(newstartDate.getDate() - 1);
var startDate = newstartDate.toISOString().slice(0, 10); // To get the Yesterday's Date in YYYY MM DD Format
alert(startDate);

不幸的是，JavaScript的Date对象有很多陷阱。任何基于Date内置toISOString的解决方案都必须打乱时区，这一点在这个问题的其他一些答案中已经讨论过。表示ISO-8601日期(没有时间)的干净解决方案是由Temporal提供的。来自Temporal提案的PlainDate。从2021年2月起，你必须选择最适合你的变通方法。

使用日期与香草字符串连接

假设您的内部表示基于Date，您可以手动执行字符串连接。下面的代码避免了Date的一些缺陷(时区、从零开始的月份、缺少2位数格式)，但可能还存在其他问题。

function vanillaToDateOnlyIso8601() {
  // month May has zero-based index 4
  const date = new Date(2014, 4, 11);

  const yyyy = date.getFullYear();
  const mm = String(date.getMonth() + 1).padStart(2, "0"); // month is zero-based
  const dd = String(date.getDate()).padStart(2, "0");

  if (yyyy < 1583) {
    // TODO: decide how to support dates before 1583
    throw new Error(`dates before year 1583 are not supported`);
  }

  const formatted = `${yyyy}-${mm}-${dd}`;
  console.log("vanilla", formatted);
}

使用Date和helper库(例如formatISO from Date -fns)

这是一种流行的方法，但您仍然被迫将日历日期作为date来处理，它表示

一个独立于平台格式的单一时刻

下面的代码应该可以完成这项工作:

import { formatISO } from "date-fns";

function dateFnsToDateOnlyIso8601() {
  // month May has zero-based index 4
  const date = new Date(2014, 4, 11);
  const formatted = formatISO(date, { representation: "date" });
  console.log("date-fns", formatted);
}

找到一个正确表示日期和时间的库

我希望有一个干净的、经过实战考验的库，它能带来自己设计良好的日期-时间表示。对于这个问题中的任务，一个很有希望的候选者是@js-joda/core中的LocalDate，但是这个库不如date-fns活跃。在处理一些示例代码时，在添加可选的@js-joda/timezone后，我也遇到了一些问题。

然而，核心功能在我看来非常干净:

import { LocalDate, Month } from "@js-joda/core";

function jodaDateOnlyIso8601() {
  const someDay = LocalDate.of(2014, Month.MAY, 11);
  const formatted = someDay.toString();
  console.log("joda", formatted);
}

用时间提案填充实验

不建议在生产环境中使用，但是如果你愿意，你可以导入future:

import { Temporal } from "proposal-temporal";

function temporalDateOnlyIso8601() {
  // yep, month is one-based here (as of Feb 2021)
  const plainDate = new Temporal.PlainDate(2014, 5, 11);
  const formatted = plainDate.toString();
  console.log("proposal-temporal", formatted);
}

你可以在Date对象上使用toLocaleDateString('fr-CA')

console.log（new Date（'Sun May 11，2014'）.toLocaleDateString（'fr-CA'））;

我还发现，这些地区给正确的结果从这个地区列表所有地区和他们的短代码列表?

'en-CA'
'fr-CA'
'lt-LT'
'sv-FI'
'sv-SE'

var localesList = ["af-ZA", "am-ET", "ar-AE", "ar-BH", "ar-DZ", "ar-EG", "ar-IQ", "ar-JO", "ar-KW", "ar-LB", "ar-LY", "ar-MA", "arn-CL", "ar-OM", "ar-QA", "ar-SA", "ar-SY", "ar-TN", "ar-YE", "as-IN", "az-Cyrl-AZ", "az-Latn-AZ", "ba-RU", "be-BY", "bg-BG", "bn-BD", "bn-IN", "bo-CN", "br-FR", "bs-Cyrl-BA", "bs-Latn-BA", "ca-ES", "co-FR", "cs-CZ", "cy-GB", "da-DK", "de-AT", "de-CH", "de-DE", "de-LI", "de-LU", "dsb-DE", "dv-MV", "el-GR", "en-029", "en-AU", "en-BZ", "en-CA", "en-GB", "en-IE", "en-IN", "en-JM", "en-MY", "en-NZ", "en-PH", "en-SG", "en-TT", "en-US", "en-ZA", "en-ZW", "es-AR", "es-BO", "es-CL", "es-CO", "es-CR", "es-DO", "es-EC", "es-ES", "es-GT", "es-HN", "es-MX", "es-NI", "es-PA", "es-PE", "es-PR", "es-PY", "es-SV", "es-US", "es-UY", "es-VE", "et-EE", "eu-ES", "fa-IR", "fi-FI", "fil-PH", "fo-FO", "fr-BE", "fr-CA", "fr-CH", "fr-FR", "fr-LU", "fr-MC", "fy-NL", "ga-IE", "gd-GB", "gl-ES", "gsw-FR", "gu-IN", "ha-Latn-NG", "he-IL", "hi-IN", "hr-BA", "hr-HR", "hsb-DE", "hu-HU", "hy-AM", "id-ID", "ig-NG", "ii-CN", "is-IS", "it-CH", "it-IT", "iu-Cans-CA", "iu-Latn-CA", "ja-JP", "ka-GE", "kk-KZ", "kl-GL", "km-KH", "kn-IN", "kok-IN", "ko-KR", "ky-KG", "lb-LU", "lo-LA", "lt-LT", "lv-LV", "mi-NZ", "mk-MK", "ml-IN", "mn-MN", "mn-Mong-CN", "moh-CA", "mr-IN", "ms-BN", "ms-MY", "mt-MT", "nb-NO", "ne-NP", "nl-BE", "nl-NL", "nn-NO", "nso-ZA", "oc-FR", "or-IN", "pa-IN", "pl-PL", "prs-AF", "ps-AF", "pt-BR", "pt-PT", "qut-GT", "quz-BO", "quz-EC", "quz-PE", "rm-CH", "ro-RO", "ru-RU", "rw-RW", "sah-RU", "sa-IN", "se-FI", "se-NO", "se-SE", "si-LK", "sk-SK", "sl-SI", "sma-NO", "sma-SE", "smj-NO", "smj-SE", "smn-FI", "sms-FI", "sq-AL", "sr-Cyrl-BA", "sr-Cyrl-CS", "sr-Cyrl-ME", "sr-Cyrl-RS", "sr-Latn-BA", "sr-Latn-CS", "sr-Latn-ME", "sr-Latn-RS", "sv-FI", "sv-SE", "sw-KE", "syr-SY", "ta-IN", "te-IN", "tg-Cyrl-TJ", "th-TH", "tk-TM", "tn-ZA", "tr-TR", "tt-RU", "tzm-Latn-DZ", "ug-CN", "uk-UA", "ur-PK", "uz-Cyrl-UZ", "uz-Latn-UZ", "vi-VN", "wo-SN", "xh-ZA", "yo-NG", "zh-CN", "zh-HK", "zh-MO", "zh-SG", "zh-TW", "zu-ZA" ]; localesList.forEach(lcl => { if ("2014-05-11" === new Date('Sun May 11,2014').toLocaleDateString(lcl)) { console.log(lcl, new Date('Sun May 11,2014').toLocaleDateString(lcl)); } });

这对我来说很有效，如果需要测试，你可以直接将它粘贴到你的HTML中:

<script type="text/javascript">
    if (datefield.type!="date"){ // If the browser doesn't support input type="date",
                                 // initialize date picker widget:
        jQuery(function($){ // On document.ready
            $('#Date').datepicker({
                dateFormat: 'yy-mm-dd', // THIS IS THE IMPORTANT PART!!!
                showOtherMonths: true,
                selectOtherMonths: true,
                changeMonth: true,
                minDate: '2016-10-19',
                maxDate: '2016-11-03'
            });
        })
    }
</script>