ansaurus

Question

JAVASCRIPT - dateobj.getTime for a UID - Is the length not fixed?

Answer 1

+1 A:

There one implementation here: http://blog.shkedy.com/2007/01/createing-guids-with-client-side.html

Here it is in action: http://jsfiddle.net/7sXL6/

I threw together a smaller version of it: http://jsfiddle.net/7sXL6/4/

Andir 2010-07-13 23:31:18

Thanks, that seems like a lot of code for a semi-elegant solution. Thoughts?

AnApprentice 2010-07-13 23:34:22

Really all it's doing is generating 32 random characters plus hyphens... there are many ways to do it, but this one fits the mold of a GUID. You could strip out some of the specific formatting if it's not needed. If you wanted to use the time, you'd have to pad zeros to the front to make it a specific length.

Andir 2010-07-13 23:38:17

Instead of moving to another so so solution I'm curious, do you know why getTime would be providing a variable length?

AnApprentice 2010-07-13 23:45:44

getDate returns the number of milliseconds since midnight, Jan 1, 1970. If one of the clients set their clock to Jan 2, 1970 you will get a very low number. See here: http://jsfiddle.net/7sXL6/3/

Andir 2010-07-13 23:56:12

Thanks Is there a way to always make sure it's at least 10 characters?

AnApprentice 2010-07-15 00:15:40

You would have to pad zeros to the front of it. See this: http://jsfiddle.net/DwPFA/

Andir 2010-07-15 00:31:52

Answer 2

+1 A:

I like doing Math.random().toString(36).substr(2,9)

antimatter15 2010-07-13 23:56:28

That works too ;)

Andir 2010-07-14 00:06:33

Very cool, so what exactly is code doing? A little explanation would be cool and probably help tons of people that find this page in the SERPS. thxs

AnApprentice 2010-07-14 16:21:35

interesting, problem is it needs to be all integers, no characters. Can that be modified above?

AnApprentice 2010-07-15 00:15:15

If you just want integers, you can get rid of the number 36, so it would become Math.random().toString().substr(2,9)In Javascript, when you're converting from a number to a string with .toString(), you can specify a base for conversion. Like (2).toString(2) would return the binary "10", and 36 just means 0123456789abcdefghijklmnopqrstuvwxyz (0-9 + a-z = 36). It can convert fractional parts too. So you end up after the string to something like "0.634k072981xde7b9" and substr(2,9) makes it a nine-letter string ignoring the starting "0.".

antimatter15 2010-07-15 18:03:58

ansaurus

tags:

views:

answers:

JAVASCRIPT - dateobj.getTime for a UID - Is the length not fixed?

related questions