str_shuffle()

(PHP 4 >= 4.3.0, PHP 5, PHP 7)

随机打乱一个字符串

说明

str_shuffle()函数打乱一个字符串，使用任何一种可能的排序方案。

本函数并不会生成安全加密的值，不应用于加密用途。若需要安全加密的值，考虑使用openssl_random_pseudo_bytes()。

参数

输入字符串。

返回值

返回打乱后的字符串。

更新日志

范例

Example #1str_shuffle()范例

参见

• shuffle()打乱数组
• rand()产生一个随机整数

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It may be ufseul if you wnat to cetare an aessblicce CTCPAHA.

This function is affected by srand():

A proper unicode string shuffle;

$str = "Şeker yârim"; // My sweet love
echo str_shuffle($str); // ieymrŢekr 
echo str_shuffle_unicode($str); // Şr mreyeikâ

This page is missing a very important notice:
Caution
This function does not generate cryptographically secure values, and should not be used for cryptographic purposes. If you need a cryptographically secure value, consider using random_int(), random_bytes(), or openssl_random_pseudo_bytes() instead.

Shuffle for all encoding formats

/**
 * Test shuffleString
 */
function testShuffleString() {
  $shuffled = shuffleString("ĄęźćÓ");
  if (\mb_strlen($shuffled) != 5) {
    throw new \UnexpectedValueException("Invalid count of characters");
  }
  if ($shuffled == "ĄęźćÓ") {
    throw new \UnexpectedValueException("The same string");
  }
  foreach (["Ą", "ę", "ź", "ć", "Ó"] as $char) {
    if (\mb_strpos($shuffled, $char) === false) {
      throw new \UnexpectedValueException("Character not found");
    }
  }
}
/**
 * Shuffle string
 *
 * @param $stringValue String to shuffle
 * @param string $startWith Shuffle $stringValue and append to $startWith
 * @return string Shuffled string
 * @author Krzysztof Piasecki
 */
function shuffleString($stringValue, $startWith = "") {
  $range = \range(0, \mb_strlen($stringValue));
  shuffle($range);
  foreach($range as $index) {
    $startWith .= \mb_substr($stringValue, $index, 1);
  }
  return $startWith;
};
testShuffleString();
echo shuffleString("Hello"); // > 'elHol' (something like this)
echo shuffleString("World!", "Hello "); // > 'Hello do!lrW' (something like this)

As noted in this documentation str_shuffle is NOT cryptographically secure, however I have seen many code examples online of people using nothing more than this to generate say random passwords. So I though I'd share my function which while it makes use of str_shuffle also rely's on random_int() for added security. I use this function to generate salts to use when working with hashes but it can also be used to generate default passwords for new users for example.
It starts with a universe of possible characters, in this case all letters (upper and lower case), 0-9, and several special characters.
It then will run str_shuffle on the universe of characters a random number of times, using random_int() (currently set to 1-10)
Then once the universe of possible characters has been shuffled it using random_int() once more to select the character as a random position within the shuffled string, as does that once for each character you want in the output.
 function secret_gen( $len=64 ) {
  $secret = "";
  $charset = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!@#$%^&*()_-+=`~,.[]:  | ';
  for ( $x = 1l $x