如何随机混淆以“/”分隔的 URL 部分？

Question

我想知道如何将这个 URL 的各个部分混杂成/ 作为分隔符：

http://fujifilm.in/en/products/consumer_products/digital_cameras/x/fujifilm_x_t1/

我正在寻找所有结果组合，例如

http://fujifilm.in/en/products/consumer_products/digital_cameras/x/fujifilm_x_t1/
http://fujifilm.in/en/products/consumer_products/digital_cameras/x
http://fujifilm.in/en/products/consumer_products/digital_cameras
http://fujifilm.in/en/products/consumer_products
http://fujifilm.in/en/products
http://fujifilm.in/en/
http://fujifilm.in/
http://fujifilm.in/en/fujifilm_x_t1/
http://fujifilm.in/en/products/fujifilm_x_t1/
http://fujifilm.in/en/products/consumer_products/fujifilm_x_t1/
http://fujifilm.in/en/products/consumer_products/digital_cameras/fujifilm_x_t1/
................
................
................

我该怎么做？

Answer 1

这应该让你开始：

$uri = 'http://fujifilm.in/en/products/consumer_products/digital_cameras/x/fujifilm_x_t1/';

$parts = parse_url($uri);
$path = $parts['path'];
$sections = explode('/', $path);
foreach ($sections as $k => $v) {
    if (!$v) {
        unset($sections[$k]);
    }
}
shuffle($sections);
echo $parts['scheme'] . '://' . $parts['host'] . '/' . implode('/', $sections) . '/' . PHP_EOL;

以上仅输出 URL 路径的一种随机排列。调整shuffle() 函数以提供所有可能的输出，然后将echo 放入foreach 循环中应该相当简单。为了让您开始，这里有一个关于 getting all possible permutations of a string 的问题。将其更改为使用数组应该不会太难。

Answer 2

我不确定它是否真的是您想要的（由于您的评论），但为未来的访问者回答这个问题：

<?php

function jumbleUrl($url) {
  // $jumbledUrls will be our result array  
  $jumbledUrls = array();

  // first strip and backup the domain and protocol
  $protocol = substr($url,0,stripos($url,'//')+2);
  $urlRemaining = substr($url,strlen($protocol));

  $domain = substr($urlRemaining,0,stripos($urlRemaining,'/')+1);
  $urlRemaining = trim(substr($urlRemaining,strlen($domain)),'/');

  // create array of remaining url parts
  $jumbleParts = explode('/',$urlRemaining);

  /**
   * now we use our jumbleable parts as numbers in our own number system and 
   * count thru all possibilities. See Text below.
   */
  $jumblePartsCount = count($jumbleParts);
  $possibilities = pow($jumblePartsCount,$jumblePartsCount);

  for ($i = 0; $i <= $possibilities; $i++) {
    // now we have to find the combination representing our number.
    // basically we have to convet our base 10 number to our base $possibilities number
    // Luckily php has a function for that:
    $possibilityNr = base_convert ( $i , 10 , count($jumbleParts) );

    // Now we take each "digit" of our possibilites Nr and take the 
    // jumbleablePart it represents
    $jumbledUrl = '';

    /** 
     * assuming you do not want jumbled urls like example.org/peter/peter/frank we
     * prevent parts from occuring more than once in an url.
     */
    $doublesPreventer = array();
    $doublesOccured   = false;
    for ($j=0;$j < strlen($possibilityNr);$j++) {
        $digit = intval(substr($possibilityNr,$j,1));
        if(in_array($digit,$doublesPreventer)) {
          $doublesOccured = true;
          break;
        }
        else {
          $jumbledUrl .= $jumbleParts[$digit].'/';
          $doublesPreventer[] = $digit;
        }
    }

    if(!$doublesOccured) {
    // Now we have a jumbled url and store it to our array of jumbled urls
        $jumbledUrls[] = $protocol . $domain . $jumbledUrl;

    }
  }

  return $jumbledUrls;
}

$url = 'http://fujifilm.in/en/products/consumer_products/digital_cameras/x/fujifilm_x_t1/';
$jumbledUrls = jumbleUrl($url);

var_dump($jumbledUrls);

查看运行 here 的代码（由于 ideone 内存限制可能无法工作）。

如果您将杂乱无章的部分视为数字，则可以轻松计算出有多少可能性。如果您有 10 个部分，那么您的数字系统保持不变，并且您有一个 10 位长的数字代表您的可能性：9,999.999.999 + 1 个可能性，对吗？

如果你有更少，让我们说像你的例子中的 6 个部分，你有 6^6 种可能性 (46656)。

继续阅读...

• Radix
• Combinatorics
• base_convert
• explode
• substr
• stripos
• 和trim

...了解它的工作原理。

警告：由于 PHP base_convert 方法的限制，它仅适用于斜线不超过 36 个（混乱部分）的情况。