note 96898 added to function.uniqid
| From: | EnricoPallazzo at osu1 dot php dot net | Date: | Sun, 21 Mar 2010 22:45:33 +0000 |
| Subject: | note 96898 added to function.uniqid | ||
| Groups: | php.notes | ||
| Request: | Send a blank email to php-notes+get-167283@lists.php.net to get a copy of this message | ||
Running:
rand_uniqid(9007199254740989);
will return 'PpQXn7COf' and:
rand_uniqid('PpQXn7COf', true);
will return '9007199254740989'
---
If you want the rand_uniqid to be at least 6 letter long, use the $pad_up = 6 argument
---
You can support even more characters (making the resulting rand_uniqid even smaller) by adding
characters to the $index var at the top of the function body.
---
<?php
function rand_uniqid($in, $to_num = false, $pad_up = false, $passKey = null)
{
$index = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if ($passKey !== null) {
// Although this function's purpose is to just make the
// ID short - and not so much secure,
// you can optionally supply a password to make it harder
// to calculate the corresponding numeric ID
for ($n = 0; $n<strlen($index); $n++) {
$i[] = substr( $index,$n ,1);
}
$passhash = hash('sha256',$passKey);
$passhash = (strlen($passhash) < strlen($index))
? hash('sha512',$passKey)
: $passhash;
for ($n=0; $n < strlen($index); $n++) {
$p[] = substr($passhash, $n ,1);
}
array_multisort($p, SORT_DESC, $i);
$index = implode($i);
}
$base = strlen($index);
if ($to_num) {
// Digital number <<-- alphabet letter code
$in = strrev($in);
$out = 0;
$len = strlen($in) - 1;
for ($t = 0; $t <= $len; $t++) {
$bcpow = bcpow($base, $len - $t);
$out = $out + strpos($index, substr($in, $t, 1)) * $bcpow;
}
if (is_numeric($pad_up)) {
$pad_up--;
if ($pad_up > 0) {
$out -= pow($base, $pad_up);
}
}
$out = sprintf('%F', $out);
$out = substr($out, 0, strpos($out, '.'));
} else {
// Digital number -->> alphabet letter code
if (is_numeric($pad_up)) {
$pad_up--;
if ($pad_up > 0) {
$in += pow($base, $pad_up);
}
}
$out = "";
for ($t = floor(log($in, $base)); $t >= 0; $t--) {
$bcp = bcpow($base, $t);
$a = floor($in / $bcp) % $base;
$out = $out . substr($index, $a, 1);
$in = $in - ($a * $bcp);
}
$out = strrev($out); // reverse
}
return $out;
}
echo rand_uniqid(1);
?>
----
Server IP: 69.147.83.197
Probable Submitter: 82.173.79.139
----
Manual Page -- http://www.php.net/manual/en/function.uniqid.php
Edit -- https://master.php.net/note/edit/96898
Del: integrated -- https://master.php.net/note/delete/96898/integrated
Del: useless -- https://master.php.net/note/delete/96898/useless
Del: bad code -- https://master.php.net/note/delete/96898/bad+code
Del: spam -- https://master.php.net/note/delete/96898/spam
Del: non-english -- https://master.php.net/note/delete/96898/non-english
Del: in docs -- https://master.php.net/note/delete/96898/in+docs
Del: other reasons-- https://master.php.net/note/delete/96898
Reject -- https://master.php.net/note/reject/96898
Search -- https://master.php.net/manage/user-notes.php