I made a class a while ago, which generates strings from id's and id's from strings. The coding is pretty crappy, but I was just beginning with php then, so please spare me :).
Here it is:
PHP Code:
<?php
class GenID {
// array of usable characters, mix them together to get more random results
// you can add uppercase chars to increase the number of possibilities
private $useChars = array(
26 => 'a',
11 => 'b',
8 => 'c',
20 => 'd',
10 => 'e',
18 => 'f',
25 => 'g',
3 => 'h',
30 => 'i',
5 => 'j',
32 => 'k',
1 => 'l',
23 => 'm',
14 => 'n',
28 => 'o',
16 => 'p',
33 => 'q',
4 => 'r',
19 => 's',
6 => 't',
21 => 'u',
29 => 'v',
34 => 'w',
24 => 'x',
0 => 'y',
12 => 'z',
27 => 1,
15 => 2,
22 => 3,
9 => 4,
31 => 5,
2 => 6,
17 => 7,
13 => 8,
35 => 9,
7 => 0
);
// reserved id's with the id that generates it as key
private $reserved = array(
'home' => 177094,
'index' => 51067968,
'user' => 1004764,
'users' => 36171523,
'admin' => 44634038,
'porn' => 782942,
'about' => 44220282,
'id' => 1100,
'get' => 32766,
'in' => 1094,
'out' => 37050,
'search' => 1166872035
);
private $linkCCount;
private static $instance;
private function __clone() {}
public static function get($id) {
if(self::$instance === null) {
self::$instance = new GenID;
}
return self::$instance->run($id);
}
private function run($id) {
if(is_string($id)) {
return $this->strtoid($id);
} else {
$id = intval($id);
return $this->idtostr($id);
}
}
private function fixId($id) {
if(in_array($id, $this->reserved)) {
$nid = $id+1;
return $this->fixId($nid);
} else {
return (int)$id;
}
}
private function clean($url) {
return preg_replace('/([\W\s])/', '', $url);
}
private function idtostr($id, $nofix = false) {
if($nofix == false) {
$id = $this->fixId($id);
}
if(!isset($this->linkCCount)) {
$this->linkCCount = count($this->useChars);
}
$this->link = '';
$this->idtostrsub($id);
return strrev($this->link);
}
private function strtoid($str) {
if(!isset($this->linkCCount)) {
$this->linkCCount = count($this->useChars);
}
$str = strtolower($str);
$str = $this->clean($str);
if(strlen($str) === 0) {
return false;
} elseif(strlen($str) === 1) {
return array_search($str, $this->useChars);
}
$chars = array();
foreach(str_split($str) as $k => $v) {
if(in_array($v, $this->useChars)) {
$chars[] = array_search($v, $this->useChars);
}
}
$s = $chars[0];
unset($chars[0]);
// start the math
foreach($chars as $char) {
$s = ($s * $this->linkCCount) + $char;
}
return $s;
}
private function idtostrsub($id) {
$id = (int)$id;
// if the id is smaller then the amount of chars just give it a char
if($id < $this->linkCCount && $id >= 0) {
if($id == $this->linkCCount) $id = 0;
$this->link .= $this->useChars[$id];
} else {
// devide the id by the amount of chars
$flr = floor($id / $this->linkCCount);
$res = $id - ($flr * $this->linkCCount);
if($res == $this->linkCCount) { $res = 0; }
$this->link .= $this->useChars[$res];
$this->link .= ($flr < $this->linkCCount && $flr >= 0)?
/* true */ $this->useChars[$flr] :
/* false */ $this->idtostrsub($flr);
}
}
}
/* Example Usage */
$id = GenID::get('henkifsf'); // result: 257762013534
$str = GenID::get(54646446); // result: ks4pi
?>
It saves a lot of characters, as you can see in the example the id: 257762013534 has the string 'henkifsf'. |
