我有一个日期,格式是2014年5月11日太阳。如何使用JavaScript将其转换为2014-05-11 ?

函数taskDate(dateMilli) { var d = (new Date(dateMilli) + ")。分割(' '); D [2] = D [2] + ','; 返回[d[0], d[1], d[2], d[3]]。加入(' '); } var datemilli =日期。解析(' 2014年5月11日'); console.log (taskDate (datemilli));

上面的代码给了我相同的日期格式,2014年5月11日。我该如何解决这个问题?


当前回答

将日期转换为yyyy-mm-dd格式的最简单方法是这样做:

var date = new Date("Sun May 11,2014");
var dateString = new Date(date.getTime() - (date.getTimezoneOffset() * 60000 ))
                    .toISOString()
                    .split("T")[0];

工作原理:

new Date("Sun May 11,2014") converts the string "Sun May 11,2014" to a date object that represents the time Sun May 11 2014 00:00:00 in a timezone based on current locale (host system settings) new Date(date.getTime() - (date.getTimezoneOffset() * 60000 )) converts your date to a date object that corresponds with the time Sun May 11 2014 00:00:00 in UTC (standard time) by subtracting the time zone offset .toISOString() converts the date object to an ISO 8601 string 2014-05-11T00:00:00.000Z .split("T") splits the string to array ["2014-05-11", "00:00:00.000Z"] [0] takes the first element of that array


Demo

var date =新日期(“太阳5月11日”); var dateString =新日期(日期。 toISOString()。 斯普利特(“T”)[0]; 游戏机。log (dateString);

注意:

The first part of the code (new Date(...)) may need to be tweaked a bit if your input format is different from that of the OP. As mikeypie pointed out in the comments, if the date string is already in the expected output format and the local timezone is west of UTC, then new Date('2022-05-18') results in 2022-05-17. And a user's locale (eg. MM/DD/YYYY vs DD-MM-YYYY) may also impact how a date is parsed by new Date(...). So do some proper testing if you want to use this code for different input formats.

其他回答

2020的答案

你可以使用本地的. tolocaledatestring()函数,它支持一些有用的参数,如区域设置(选择MM/DD/YYYY或YYYY/MM/DD格式),时区(转换日期)和格式详细选项(例如:1 vs 01 vs一月)。

例子

const testCases = [ new Date().toLocaleDateString(), // 8/19/2020 new Date().toLocaleString(undefined, {year: 'numeric', month: '2-digit', day: '2-digit', weekday:"long", hour: '2-digit', hour12: false, minute:'2-digit', second:'2-digit'}), new Date().toLocaleDateString('en-US', {year: 'numeric', month: '2-digit', day: '2-digit'}), // 08/19/2020 (month and day with two digits) new Date().toLocaleDateString('en-ZA'), // 2020/08/19 (year/month/day) notice the different locale new Date().toLocaleDateString('en-CA'), // 2020-08-19 (year-month-day) notice the different locale new Date().toLocaleString("en-US", {timeZone: "America/New_York"}), // 8/19/2020, 9:29:51 AM. (date and time in a specific timezone) new Date().toLocaleString("en-US", {hour: '2-digit', hour12: false, timeZone: "America/New_York"}), // 09 (just the hour) ] for (const testData of testCases) { console.log(testData) }

注意,有时要以特定的格式输出日期,必须找到与该格式兼容的区域设置。 您可以在这里找到本地示例:https://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_tolocalestring_date_all

请注意locale只是改变格式,如果你想将特定日期转换为特定国家或城市的等效时间,那么你需要使用timezone参数。

Date.js很适合这个。

require("datejs")
(new Date()).toString("yyyy-MM-dd")

如果日期需要在所有时区都相同,例如表示数据库中的某个值,那么请确保在JavaScript date对象上使用UTC版本的日、月、年函数,因为这将以UTC时间显示,并避免在某些时区出现差一的错误。

更好的是,使用Moment.js日期库来进行这种格式设置。

我有一个关于这个问题的提纲

dateInstance.toLocaleDateString().replaceAll("/", "-").split("-").reverse().join("-");

将日期转换为yyyy-mm-dd格式的最简单方法是这样做:

var date = new Date("Sun May 11,2014");
var dateString = new Date(date.getTime() - (date.getTimezoneOffset() * 60000 ))
                    .toISOString()
                    .split("T")[0];

工作原理:

new Date("Sun May 11,2014") converts the string "Sun May 11,2014" to a date object that represents the time Sun May 11 2014 00:00:00 in a timezone based on current locale (host system settings) new Date(date.getTime() - (date.getTimezoneOffset() * 60000 )) converts your date to a date object that corresponds with the time Sun May 11 2014 00:00:00 in UTC (standard time) by subtracting the time zone offset .toISOString() converts the date object to an ISO 8601 string 2014-05-11T00:00:00.000Z .split("T") splits the string to array ["2014-05-11", "00:00:00.000Z"] [0] takes the first element of that array


Demo

var date =新日期(“太阳5月11日”); var dateString =新日期(日期。 toISOString()。 斯普利特(“T”)[0]; 游戏机。log (dateString);

注意:

The first part of the code (new Date(...)) may need to be tweaked a bit if your input format is different from that of the OP. As mikeypie pointed out in the comments, if the date string is already in the expected output format and the local timezone is west of UTC, then new Date('2022-05-18') results in 2022-05-17. And a user's locale (eg. MM/DD/YYYY vs DD-MM-YYYY) may also impact how a date is parsed by new Date(...). So do some proper testing if you want to use this code for different input formats.