javascript - 在JavaScript中创建GUID / UUID？(Create GUID / UUID in JavaScript?)

Question

I'm trying to create globally-unique identifiers in JavaScript.

(我正在尝试在JavaScript中创建全局唯一标识符。)

I'm not sure what routines are available on all browsers, how "random" and seeded the built-in random number generator is, etc..

(我不确定所有浏览器上都提供哪些例程，内置随机数生成器的“随机性”和种子状态如何，等等。)

The GUID / UUID should be at least 32 characters and should stay in the ASCII range to avoid trouble when passing them around.

(GUID / UUID至少应包含32个字符，并且应保持在ASCII范围内，以免在传递它们时遇到麻烦。)

  ask by community wiki translate from so

Answer 1

For an RFC4122 version 4 compliant solution, this one-liner(ish) solution is the most compact I could come up with:

(对于符合RFC4122版本4的解决方案，此一站式解决方案是我能想到的最紧凑的解决方案：)

 function uuidv4() { return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) { var r = Math.random() * 16 | 0, v = c == 'x' ? r : (r & 0x3 | 0x8); return v.toString(16); }); } console.log(uuidv4()); 

Update, 2015-06-02 : Be aware that UUID uniqueness relies heavily on the underlying random number generator (RNG).

(更新，2015-06-02 ：请注意，UUID的唯一性很大程度上取决于基础随机数生成器（RNG）。)

The solution above uses Math.random() for brevity, however Math.random() is not guaranteed to be a high-quality RNG.

(上面的解决方案为简洁起见使用Math.random() ，但是不能保证Math.random()是高质量的RNG。)

See Adam Hyland's excellent writeup on Math.random() for details.

(有关详细信息，请参见Adam Hyland 在Math.random（）上的出色文章 。)

For a more robust solution, consider something like the uuid module (disclaimer: I'm the author), which uses higher quality RNG APIs where available.

(对于更强大的解决方案，请考虑使用uuid模块 （免责声明：我是作者）之类的东西， 该模块在可用时使用更高质量的RNG API。)

Update, 2015-08-26 : As a side-note, this gist describes how to determine how many IDs can be generated before reaching a certain probability of collision.

(更新，2015-08-26 ：作为旁注，本要点描述了如何确定在达到一定的碰撞概率之前可以生成多少个ID。)

For example, with 3.26x10 ¹⁵ version 4 RFC4122 UUIDs you have a 1-in-a-million chance of collision.

(例如，使用3.26x10 ¹⁵版本4 RFC4122 UUID，您有百万分之一的碰撞机会。)

Update, 2017-06-28 : A good article from Chrome developers discussing the state of Math.random PRNG quality in Chrome, Firefox, and Safari.

(更新，2017-06-28 ： Chrome开发人员的一篇好文章，讨论了Chrome，Firefox和Safari中Math.random PRNG的质量状态。)

tl;dr - As of late-2015 it's "pretty good", but not cryptographic quality.

(tl; dr-截至2015年末，它的“相当好”，但没有加密质量。)

To address that issue, here's an updated version of the above solution that uses ES6, the crypto API, and a bit of JS wizardry I can't take credit for :

(为了解决该问题，这是上述解决方案的更新版本，该解决方案使用ES6， crypto API和一些JS向导，我对此不以为然 ：)

 function uuidv4() { return ([1e7]+-1e3+-4e3+-8e3+-1e11).replace(/[018]/g, c => (c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16) ); } console.log(uuidv4());