blocks|key|1495997|text|首先，这是一个很好的问题。许多开发人员使用日期，但从来不去问它到底是如何工作的。是的，它是运行JavaScript引擎所基于的机器，所以它也依赖于时区。请参阅：https://javascript.info/date|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1495998|entityMap|0|LINK|mutability|MUTABLE|url|https://javascript.info/date^0|28|S|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

First of all its a very good question. Lot of developers use date but never bother to go as to how it works exactly.
Yes, it's machine based on which the JavaScript engine is running, so yes it depends upon timezone too.
See : <a href="https://javascript.info/date" rel="nofollow noreferrer">https://javascript.info/date</a>

blocks|key|861908|text|根据mdn，准确的日期/小时是基于您的计算机。更多细节：对象/日期/getHours|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|861909|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getHours^0|S|E|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

According to mdn, the exact date/hour is based on your computer. More details:
<a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getHours" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getHours</a>

blocks|key|1496010|text|这是基于Unix时间戳，如果被请求的客户端则基于用户的计算机时间，如果请求服务器端则基于服务器时间戳。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1496011|关于进一步的理解，见：|1496012|对象/日期/现在|offset|length|1496013|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now^0|0|0|0|8|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@$F|S|G|T|1|U]]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

This is based on the Unix timestamp and will be based on the users' computers time if requested client-side, or the servers timestamp if requested server-side.

For further reading see:

<a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now</a>

blocks|key|861958|text|Javascript在web浏览器上运行，因此它需要用户机器的时间。因此，如果您的用户坐在不同的时区，那么他们将看到不同的时间。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|861959|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Javascript runs on a web browser so it will take the time form the user's machine. So if your users sit in different time zone then they will see different time.

blocks|key|1706922|text|Javascript在客户端执行！因此，是的，每个用户都会看到他的机器时间和他的特定时区。即使用户在他的机器上有错误的时间，他也会认为它是错误的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1706923|例如，当您使用Node.js时，异常返回服务器时间。在这种情况下，本地时间将是服务器时间。同样，在服务器上，时间和时区通常遵循OS时间设置。|1706924|如果你希望他们都能看到同样的时间，比如：“伦敦时间:晚上10点13分”|1706925|您需要使用服务器的编程语言将服务器时间存储在javascript变量中。|1706926|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|L|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|M|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

Javascript Date is executed on the client side ! So yes each user would see his machine time and his specific Timezone.
Even when the user has a wrong time in his machine, he would see it wrong.

The exception returns Server time when you are using Node.js for example. In that case, local time would be the server time.
Again on servers, usually time and Timezones follow the OS time setting.

If you expect them all to see the same time, Like displaying : "Time in London 10:13pm"

You need to store your server time in a javascript variable using your server' programming language.

blocks|key|862069|text|在您提供的代码中，第一行是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|862070|var+currentdate+=+new+Date();|code-block|syntax|javascript|862071|Date对象的构造函数是在没有任何参数的情况下调用的，因此使用与Date.now()值相同的时间戳进行初始化。该值是一个Unix时间戳，包含自1970-01-01+00:00:00.000+UTC以来的毫秒(不考虑闰秒)。它是严格基于UTC的。系统时区不涉及构造，Date对象不存储系统时区。|offset|length|style|CODE|862072|只涉及系统时钟。每个计算机系统都有一个内部时钟，可以返回当前的UTC时间。此时钟通常通过NTP、PPTP或类似机制与其他计算机的时钟同步。不过，它依赖于计算机。例如，当配置为“自动设置时间”时，Windows计算机将从Internet上的公共NTP服务器或本地网络上的域控制器(取决于网络配置)获得它们的时间。但是，未配置为自动设置时间的独立计算机可能具有非常不同的时钟值。|862073|因此，两台调用new+Date()+(或Date.now())的给定计算机可能会检索类似的值，如果它们的时钟同步正确，但不能保证同步。不涉及网络呼叫，只需呼叫本地系统时钟。|862074|在剩下的代码中，您将调用函数getMonth、getFullYear、getHours、getMinutes和getSeconds。每个函数调用都将独立地使用Date对象的基于UTC的时间戳和在执行代码的计算机上配置的时区。如果代码是在web浏览器中执行的，则应用的是用户计算机的时区。如果代码是在服务器上执行的，那么应用的就是服务器的时区。|862075|同样，重要的是要记住的是，Date对象只跟踪一个数字值--自Unix时代以来的毫秒(不包括闰秒)。您可以通过在d.getTime()对象上调用d.valueOf()或Date对象(此处命名为d+)直接看到这个值，或者强制将该值强制为一个数字，如%2Bd中的。时区不是对象状态的一部分，也不自行进行网络调用。|862076|entityMap|0|LINK|mutability|MUTABLE|url|https://en.wikipedia.org/wiki/Unix_time|1|https://en.wikipedia.org/wiki/Coordinated_Universal_Time^0|0|0|0|4|W|A|1Z|R|3O|4|1O|7|0|39|3|1|0|0|7|A|K|A|0|E|8|N|B|Z|8|18|A|1J|A|27|4|0|D|4|1J|B|1Z|B|2B|4|2N|1|3E|2|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|16|8|@$I|17|J|18|K|L]|$I|19|J|1A|K|L]|$I|1B|J|1C|K|L]|$I|1D|J|1E|K|L]]|9|@$I|1F|J|1G|1|1H]|$I|1I|J|1J|1|1K]]|A|$]]|$1|M|3|N|5|6|7|1L|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1M|8|@$I|1N|J|1O|K|L]|$I|1P|J|1Q|K|L]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1R|8|@$I|1S|J|1T|K|L]|$I|1U|J|1V|K|L]|$I|1W|J|1X|K|L]|$I|1Y|J|1Z|K|L]|$I|20|J|21|K|L]|$I|22|J|23|K|L]]|9|@]|A|$]]|$1|S|3|T|5|6|7|24|8|@$I|25|J|26|K|L]|$I|27|J|28|K|L]|$I|29|J|2A|K|L]|$I|2B|J|2C|K|L]|$I|2D|J|2E|K|L]|$I|2F|J|2G|K|L]]|9|@]|A|$]]|$1|U|3|-4|5|6|7|2H|8|@]|9|@]|A|$]]]|V|$W|$5|X|Y|Z|A|$10|11]]|12|$5|X|Y|Z|A|$10|13]]]]

In the code you provided, the first line is:

<pre><code>var currentdate = new Date();
</code></pre>

The constructor of the <code>Date</code> object is called without any parameters, and thus is initialized with a timestamp having the same value as <code>Date.now()</code>. That value is a <a href="https://en.wikipedia.org/wiki/Unix_time" rel="nofollow noreferrer">Unix timestamp</a>, containing milliseconds since <code>1970-01-01 00:00:00.000 UTC</code> (not accounting for leap seconds). It is strictly <a href="https://en.wikipedia.org/wiki/Coordinated_Universal_Time" rel="nofollow noreferrer">UTC</a> based. The sytem time zone is not involved in the construction, and the <code>Date</code> object does not store the system time zone.

Only the system clock is involved. Every computer system has an internal clock that can return the current UTC time. This clock is most often synchronized with clocks of other computers via NTP, PPTP, or similar mechanisms. It is computer dependent though. 
 For example, when configured for "set time automatically", Windows computers will obtain their time either from a public NTP server on the Internet, or from a domain controller on a local network, depending on the network configuration. However, a standalone computer that is not configured to set time automatically, could have a very different clock value.

Thus, two given computers calling <code>new Date()</code> (or <code>Date.now()</code>) will likely retrieve similar values if their clocks are synchronized correctly, but are not guaranteed to. There is no network call involved, only a call to the local system clock.

In the rest of your code, you call the functions <code>getMonth</code>, <code>getFullYear</code>, <code>getHours</code>, <code>getMinutes</code>, and <code>getSeconds</code>. Each of these function calls will independently use the <code>Date</code> object's UTC-based timestamp and the time zone configured on the computer where the code is being executed. If the code is executed in a web browser, then it's the user's computer's time zone that is applied. If the code is executed on the server, then it's the server's time zone that is applied.

Again, the important thing to remember is that <code>Date</code> object only track a single numeric value - the milliseconds since the Unix epoch (not accounting for leap seconds). You can see this value directly by calling <code>d.getTime()</code> or <code>d.valueOf()</code> on the <code>Date</code> object (named <code>d</code> here), or by coercing the value to a Number as in <code>+d</code>. The time zone is not part of the object's state, and it does not make network calls on its own.

I am using the date object below to obtain the current time from the user:

<pre><code> var currentdate = new Date();
 return (currentdate.getDate() + "/"
 + (currentdate.getMonth()+1) + "/"
 + currentdate.getFullYear() + " @ "
 + currentdate.getHours() + ":"
 + currentdate.getMinutes() + ":"
 + currentdate.getSeconds());
</code></pre>

My question is where does <code>currentdate</code> obtain the time from? Does it grab the time from a central server? Would any user from anywhere around the globe execute the codes above at the same time will obtain the same value?

Or this is per user based, meaning if two users from different time zones execute the codes at the same time, they will obtain the time based on their time zone, hence the codes return different values?

Javascript date object based on what

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我使用下面的date对象从用户获得当前时间：    var currentdate = new Date();    return (currentdate.getDate() + "/"            + (currentdate.getMonth()+1)  + "/"            + curre...

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