单调增加JavaScript的时间？ [英] Monotonically increasing time in JavaScript?

问题描述

在JavaScript中单调增加时间的最佳方法是什么？我希望有类似Java的 System.nanoTime（）。

What’s the best way to get monotonically increasing time in JavaScript? I’m hoping for something like Java’s System.nanoTime().

日期（ ）显然不起作用，因为它受系统时间变化的影响。

Date() obviously won’t work, as it’s affected by system time changes.

换句话说，我想要的是< = b， 始终 ：

In other words, what I would like is for a <= b, always:

a = myIncreasingTime.getMilliseconds();
...
// some time later, maybe seconds, maybe days
b = myIncreasingTime.getMilliseconds();

充其量，即使在 Date（）中使用UTC功能，它将返回它认为正确的时间，但如果有人向后设置时间，则下一次调用Date（）可以返回较小的值。 System.nanoTime（）不受此限制（至少在重新启动系统之前）。

At best, even when using the UTC functions in Date(), it will return what it believes is the correct time, but if someone sets the time backward, the next call to Date() can return a lesser value. System.nanoTime() does not suffer from this limitation (at least not until the system is rebooted).

修改：[2012-02-26：不打算影响有问题的原始问题]

Modification: [2012-02-26: not intended to affect the original question, which has a bounty]

我不感兴趣知道壁垒时间，我有兴趣知道已过去的时间有些准确， Date（）无法提供。

I am not interested knowing the "wall time", I’m interested in knowing elapsed time with some accuracy, which Date() cannot possibly provide.

推荐答案

您可以使用窗口.performance.now（） - 自Firefox 15和window.performance.webkitNow（） - Chrome 20]

You could use window.performance.now() - since Firefox 15, and window.performance.webkitNow() - Chrome 20]

var a = window.performance.now();
//...
var delay = window.performance.now() - a;

这篇关于单调增加JavaScript的时间？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！