英文:
JavaScript: How to keep the original input date format when using new Date()?
问题
我有一个日期，格式如下："2023-05-19T18:30:00.000Z"
我的代码如下：
date(value) {
const myDate = new Date("2023-05-19T18:30:00.000Z")
}
上述代码返回的日期是
"Sat May 20 2023 00:00:00 GMT+0530 (印度标准时间)"。
问题是，我的输入日期是5月19日，但在使用new Date后，它变成了5月20日。如何阻止日期和时间发生变化？
英文:
I have a date which is in following format "2023-05-19T18:30:00.000Z"
My code is as follows:
date(value) {
const myDate = new Date("2023-05-19T18:30:00.000Z")
}
Above code is giving date as
"Sat May 20 2023 00:00:00 GMT+0530 (Indian Standard Time)".
Problem is my input date is 19 May but after doing
new Date it is giving May 20. how can I stop date and time getting changed?
答案1
得分: 1
console.log(new Date("2023-05-19T18:30:00.000Z").toString())
// 你在这里使用了 [日期时间字符串格式](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#date_time_string_format) 来初始化 `Date` 对象，其中结尾的 `Z` 表示你设置了零 [UTC 偏移](https://en.wikipedia.org/wiki/UTC_offset)，因此它表示 [UTC+00:00](https://en.wikipedia.org/wiki/UTC%2B00:00) 时区。*(感谢 @RobG 的澄清。)*
// 但是，当你将 `Date` 对象转换回字符串时，它会默认为用户的本地时区，并相应地转换日期和时间，这就是为什么它们看起来不同（除非你的本地时区恰好是 UTC+00:00）。
// 要获得与 UTC+00:00 明确对应的字符串，请使用 [toUTCString()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toUTCString) 方法：
console.log(new Date("2023-05-19T18:30:00.000Z").toUTCString())
// 你也可以获取任何 `Date` 组件作为数字：
let date = new Date("2023-05-19T18:30:00.000Z");
console.log(
`Year: ${date.getUTCFullYear()},`,
`Month: ${date.getUTCMonth() + 1},`, // 注意：月份是从零开始的，所以必须加1！
`Day: ${date.getUTCDate()},`,
`Hours: ${date.getUTCHours()},`,
`Minutes: ${date.getUTCMinutes()},`,
`Seconds: ${date.getUTCSeconds()},`,
`Milliseconds: ${date.getUTCMilliseconds()}`
);
英文:
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
console.log(new Date("2023-05-19T18:30:00.000Z").toString())
<!-- end snippet -->
Here you are using Date time string format to initialize Date object, where trailing Z means you're setting it with zero UTC offset, so that it represents UTC+00:00 timezone. (Thanks to @RobG for clarification.)
However, when you're converting your Date object back into a string, it defaults to a local time zone of the user and translates date and time accordingly, which is why you're seeing them different (unless your local time zone is exactly UTC+00:00).
To obtain a string in explicit correspondence with UTC+00:00, use toUTCString() method:
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
console.log(new Date("2023-05-19T18:30:00.000Z").toUTCString())
<!-- end snippet -->
Also you can get any of the Date components as a number:
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
let date = new Date("2023-05-19T18:30:00.000Z");
console.log(
`Year: ${date.getUTCFullYear()},`,
`Month: ${date.getUTCMonth() + 1},`, // note: month is zero-based, so has to be incremented!
`Day: ${date.getUTCDate()},`,
`Hours: ${date.getUTCHours()},`,
`Minutes: ${date.getUTCMinutes()},`,
`Seconds: ${date.getUTCSeconds()},`,
`Milliseconds: ${date.getUTCMilliseconds()}`
);
<!-- end snippet -->
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论