如何在 PHP 中制作简短的随机唯一密钥，例如 YouTube 视频 ID？

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Answer 1

这个想法是将唯一整数（例如当前时间）转换为其他数学基础。

PHP 中的一个非常简单的方法：

// With this precision (microsecond) ID will looks like '2di2adajgq6h'

// From PHP 7.4.0 this is needed, otherwise a warning is displayed
$cleanNumber = preg_replace( '/[^0-9]/', '', microtime(false) );
$id = base_convert($cleanNumber, 10, 36);


// With less precision (second) ID will looks like 'niu7pj'

$id = base_convert(time(), 10, 36);

Answer 2

一个小型 PHP 类，用于从一个或多个数字生成类似 YouTube 的哈希值。当您不想向用户公开数据库 ID 时，请使用 hashids。

来源：https://github.com/ivanakimov/hashids.php

Answer 3

这是一个每次随机生成唯一密钥的小函数。重复相同唯一 ID 的机会非常少。

function uniqueKey($limit = 10) {

    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';

    $randstring = '';

    for ($i = 0; $i < $limit; $i++) {

        $randstring .= $characters[rand(0, strlen($characters))];
    }

    return $randstring;
}

Answer 4

使用您喜欢的任何一个:-)

// 生成字母数字输出

function generateRandomID() {
    // http://mohnish.in
    $required_length = 11;
    $limit_one = rand();
    $limit_two = rand();
    $randomID = substr(uniqid(sha1(crypt(md5(rand(min($limit_one, $limit_two), max($limit_one, $limit_two)))))), 0, $required_length);
    return $randomID;
}

// 只生成字母输出

function anotherRandomIDGenerator() {
    // Copyright: http://snippets.dzone.com/posts/show/3123
    $len = 8;
    $base='ABCDEFGHKLMNOPQRSTWXYZabcdefghjkmnpqrstwxyz';
    $max=strlen($base)-1;
    $activatecode='';
    mt_srand((double)microtime()*1000000);
    while (strlen($activatecode)<$len+1)
    $activatecode.=$base{mt_rand(0,$max)};
    return $activatecode;
}

Answer 5

对我来说最好的算法是这样的： 使用 PHP/Python/Javascript/Java/SQL 创建类似 Youtube 的 ID

<?php
/**
 * Translates a number to a short alhanumeric version
 *
 * Translated any number up to 9007199254740992
 * to a shorter version in letters e.g.:
 * 9007199254740989 --> PpQXn7COf
 *
 * specifiying the second argument true, it will
 * translate back e.g.:
 * PpQXn7COf --> 9007199254740989
 *
 * this function is based on any2dec && dec2any by
 * fragmer[at]mail[dot]ru
 * see: http://nl3.php.net/manual/en/function.base-convert.php#52450
 *
 * If you want the alphaID to be at least 3 letter long, use the
 * $pad_up = 3 argument
 *
 * In most cases this is better than totally random ID generators
 * because this can easily avoid duplicate ID's.
 * For example if you correlate the alpha ID to an auto incrementing ID
 * in your database, you're done.
 *
 * The reverse is done because it makes it slightly more cryptic,
 * but it also makes it easier to spread lots of IDs in different
 * directories on your filesystem. Example:
 * $part1 = substr($alpha_id,0,1);
 * $part2 = substr($alpha_id,1,1);
 * $part3 = substr($alpha_id,2,strlen($alpha_id));
 * $destindir = "/".$part1."/".$part2."/".$part3;
 * // by reversing, directories are more evenly spread out. The
 * // first 26 directories already occupy 26 main levels
 *
 * more info on limitation:
 * - http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/165372
 *
 * if you really need this for bigger numbers you probably have to look
 * at things like: http://theserverpages.com/php/manual/en/ref.bc.php
 * or: http://theserverpages.com/php/manual/en/ref.gmp.php
 * but I haven't really dugg into this. If you have more info on those
 * matters feel free to leave a comment.
 *
 * The following code block can be utilized by PEAR's Testing_DocTest
 * <code>
 * // Input //
 * $number_in = 2188847690240;
 * $alpha_in  = "SpQXn7Cb";
 *
 * // Execute //
 * $alpha_out  = alphaID($number_in, false, 8);
 * $number_out = alphaID($alpha_in, true, 8);
 *
 * if ($number_in != $number_out) {
 *   echo "Conversion failure, ".$alpha_in." returns ".$number_out." instead of the ";
 *   echo "desired: ".$number_in."\n";
 * }
 * if ($alpha_in != $alpha_out) {
 *   echo "Conversion failure, ".$number_in." returns ".$alpha_out." instead of the ";
 *   echo "desired: ".$alpha_in."\n";
 * }
 *
 * // Show //
 * echo $number_out." => ".$alpha_out."\n";
 * echo $alpha_in." => ".$number_out."\n";
 * echo alphaID(238328, false)." => ".alphaID(alphaID(238328, false), true)."\n";
 *
 * // expects:
 * // 2188847690240 => SpQXn7Cb
 * // SpQXn7Cb => 2188847690240
 * // aaab => 238328
 *
 * </code>
 *
 * @author  Kevin van Zonneveld <[email protected]>
 * @author  Simon Franz
 * @author  Deadfish
 * @author  SK83RJOSH
 * @copyright 2008 Kevin van Zonneveld (http://kevin.vanzonneveld.net)
 * @license   http://www.opensource.org/licenses/bsd-license.php New BSD Licence
 * @version   SVN: Release: $Id: alphaID.inc.php 344 2009-06-10 17:43:59Z kevin $
 * @link    http://kevin.vanzonneveld.net/
 *
 * @param mixed   $in   String or long input to translate
 * @param boolean $to_num  Reverses translation when true
 * @param mixed   $pad_up  Number or boolean padds the result up to a specified length
 * @param string  $pass_key Supplying a password makes it harder to calculate the original ID
 *
 * @return mixed string or long
 */
function alphaID($in, $to_num = false, $pad_up = false, $pass_key = null)
{
  $out   =   '';
  $index = 'abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
  $base  = strlen($index);

  if ($pass_key !== null) {
    // Although this function's purpose is to just make the
    // ID short - and not so much secure,
    // with this patch by Simon Franz (http://blog.snaky.org/)
    // 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);
    }

    $pass_hash = hash('sha256',$pass_key);
    $pass_hash = (strlen($pass_hash) < strlen($index) ? hash('sha512', $pass_key) : $pass_hash);

    for ($n = 0; $n < strlen($index); $n++) {
      $p[] =  substr($pass_hash, $n, 1);
    }

    array_multisort($p, SORT_DESC, $i);
    $index = implode($i);
  }

  if ($to_num) {
    // Digital number  <<--  alphabet letter code
    $len = strlen($in) - 1;

    for ($t = $len; $t >= 0; $t--) {
      $bcp = bcpow($base, $len - $t);
      $out = $out + strpos($index, substr($in, $t, 1)) * $bcp;
    }

    if (is_numeric($pad_up)) {
      $pad_up--;

      if ($pad_up > 0) {
        $out -= pow($base, $pad_up);
      }
    }
  } else {
    // Digital number  -->>  alphabet letter code
    if (is_numeric($pad_up)) {
      $pad_up--;

      if ($pad_up > 0) {
        $in += pow($base, $pad_up);
      }
    }

    for ($t = ($in != 0 ? floor(log($in, $base)) : 0); $t >= 0; $t--) {
      $bcp = bcpow($base, $t);
      $a   = floor($in / $bcp) % $base;
      $out = $out . substr($index, $a, 1);
      $in  = $in - ($a * $bcp);
    }
  }

  return $out;
}

Answer 6

上面的所有方法都很好，但请确保您知道并且不要假设生成的字符串是唯一的。我过去所做的是创建一个递归函数，根据我的数据库检查字符串，如果它是唯一的，则返回该值，否则它会再次运行。不过，这几乎不会发生，具体取决于您的唯一字符串的长度。 知道它的独特性真是太好了。

Answer 7

我一直在寻找一种非常快速且简单的解决方案（这并不是为了以任何方式保证安全），它可以在重新生成时复制实际的哈希代码（与 PHP 的 microtime 唯一 id 不同）。这个就成功了。

http://php.net/manual/en/book.hash.php

所以：

for($i=0;$i<count($myArray);$i++) {
    $hashCode = "#".hash('crc32b', $myArray[$i]."-".$i);        
}

产量：

#179507fa
#8e9c5640
#f99b66d6
#67fff375
#10f8c3e3

等等

我不会假装知道如何使用所有不同的哈希算法，但对于非安全用途（如链接#anchors），这很方便。

Answer 8

从此处的评论：

<?php 
function generateRandStr($length){ 
      $randstr = ""; 
      for($i=0; $i<$length; $i++){ 
         $randnum = mt_rand(0,61); 
         if($randnum < 10){ 
            $randstr .= chr($randnum+48); 
         }else if($randnum < 36){ 
            $randstr .= chr($randnum+55); 
         }else{ 
            $randstr .= chr($randnum+61); 
         } 
      } 
      return $randstr; 
   } 
?> 

Simply use: 
generateRandStr(10); 

Sample output: $%29zon(4f

您可以使用此函数来生成字母数字，或者只是字母字符。

Answer 9

对于大多数目的，uniqid 就足够了，如果你需要的话为了确保绝对不发生冲突，需要采取更复杂的措施。

Answer 10

<?php
function keygen(){
    $chars = "bcdfghjklmnpqrstvwxyz";
    $chars .= "BCDFGHJKLMNPQRSTVWXYZ";
    $chars .= "0123456789";
    while(1){
        $key = '';
        srand((double)microtime()*1000000);
        for($i = 0; $i < 10; $i++){
            $key .= substr($chars,(rand()%(strlen($chars))), 1);
        }
        break;
    }
    return $key;
}

//echo keygen();
?>