How to make "uniqid" only give numbers?

Question

I have the following code which I have put together from different tutorial examples:

<?php

$stamp = date("Ymdhis");
$random_id_length = 6;
$rndid = crypt(uniqid(rand(),1)); 
$rndid = strip_tags(stripslashes($rndid)); 
$rndid = str_replace(".","",$rndid); 
$rndid = strrev(str_replace("/","",$rndid));
$rndid = substr($rndid,0,$random_id_length); 
$orderid = "$stamp-$rndid";
$orderid = str_replace(".", "", "$orderid");
echo($orderid);

?>

FIDDLE: http://phpfiddle.org/main/code/27d-qfw

I would like this to create a number; the current time, followed by a 6 digit random number.

For example: 20130710045730-954762

However at the moment the random digits also include letters.

For example: 20130710045730-Z3sVN2

How can I edit the code to just include numbers? Any help is appreciated.

you could use `str_pad(rand(0,999999),6, "0", STR_PAD_LEFT)` you have a 1 in a million chance of a collision for posts in the same second. — Orangepill, Jul 10 '13 at 17:15

hek2mgl · Accepted Answer · 2013-10-30T14:27:16.027

uniqid() will already return numbers. But in their hexadecimal representation. In general you could just convert them to decimals:

echo hexdec(uniqid());

The value can only meaningful being observed on a 64 bit system as it is very large and beyond the limits of an 32bit signed integer (like php's one). And that's the point. uniqid() uses such large numbers together with other techniques to ensure a high grade of uniqness. If you are using only 6 digits, you cannot grant this anymore. The risk that values will collide will be high.

I would suggest to generate an application wide uniqness using an auto_increment value in a database or something similar to that.

score 5 · Answer 2 · edited May 23 '17 at 12:10

5

If it's a random string, use something like this:

$stamp = date("Ymdhis");
$random_id_length = 6;
$rndid = generateRandomString( $random_id_length );

$orderid = $stamp ."-". $rndid;
echo($orderid);

function generateRandomString($length = 10) {
  $characters = '0123456789';
  $randomString = '';
  for ($i = 0; $i < $length; $i++) {
    $randomString .= $characters[rand(0, strlen($characters) - 1)];
  }
  return $randomString;
}

// Output example: 20130710055714-462231

Example: http://codepad.org/eukiOb6S

Fn modified from https://stackoverflow.com/a/4356295/1265817

edited May 23 '17 at 12:10

Community

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answered Jul 10 '13 at 17:58

DACrosby

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Thanks! That's perefct :-) – Chris Jul 11 '13 at 09:43
No problem at all! If you find the answer to be correct, please mark it correct for future users, thanks! – DACrosby Jul 11 '13 at 13:56

score 0 · Answer 3 · answered Jul 10 '13 at 17:17

0

Use this code.I think this will be help.

rand(100000,999999)

Enter the two number which digit number do you want

answered Jul 10 '13 at 17:17

r.vengadesh

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i think both are same @ceejayoz – r.vengadesh Jul 10 '13 at 17:27
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http://php.net/mt_rand says it is, at the very least, much faster, and uses known randomness characteristics. It should be used instead of `rand()`. – ceejayoz Jul 10 '13 at 17:36

score 0 · Answer 4 · edited Jan 28 '16 at 12:39

0

Use this:

str_pad(rand(0,'9'.round(microtime(true))),11, "0", STR_PAD_LEFT);

edited Jan 28 '16 at 12:39

Tunaki

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answered Jan 28 '16 at 12:36

Jasveer Singh

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Add further explanation of why this will work and why OP wasn't getting it right – NSNoob Jan 28 '16 at 13:02
please visit this link for more details [http://php.net/manual/en/function.str-pad.php] . And round(microtime(true)) always calls the microtime.. – Jasveer Singh Jan 29 '16 at 05:27

How to make "uniqid" only give numbers?

4 Answers4

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