字符串函数
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str_shuffle

(PHP 4 >= 4.3.0, PHP 5)

str_shuffle — 随机打乱一个字符串

说明

string str_shuffle ( string $str )

str_shuffle() 函数打乱一个字符串，使用任何一种可能的排序方案。

参数

str

输入字符串。

返回值

返回打乱后的字符串。

范例

Example #1 str_shuffle() 范例

<?php
$str = 'abcdef';
$shuffled = str_shuffle($str);

// 输出类似于: bfdaec
echo $shuffled;
?>

参见

字符串函数
在线手册：中文 英文
PHP手册
PHP手册 - N: 随机打乱一个字符串

用户评论:

qeremy [atta] gmail [dotta] com (24-Feb-2012 07:58)

A proper unicode string shuffle;

<?php
function str_shuffle_unicode($str) {
    $tmp = preg_split("//u", $str, -1, PREG_SPLIT_NO_EMPTY);
    shuffle($tmp);
    return join("", $tmp);
}
?>

$str = "?eker y?rim"; // My sweet love

echo str_shuffle($str); // i?eymr?ekr ?

echo str_shuffle_unicode($str); // ?r mreyeik?

Anonymous (21-Jun-2010 06:32)

Shuffle for all encoding formats

<?php

function unicode_shuffle($string, $chars, $format = 'UTF-8')
{
    for($i=0; $i<$chars; $i++)
        $rands[$i] = rand(0, mb_strlen($string, $format));
           
        $s = NULL;
           
    foreach($rands as $r)
        $s.= mb_substr($string, $r, 1, $format);
           
    return $s;
}

?>

andre at admolin dot com (01-Apr-2010 07:11)

Here are nice functions for invert/randomize/alter the capitalization of a string.

<?php
function invert_case( $str ) {
    for( $i = 0; $i < strlen( $str ); ++$i ) {
        $ret .= ( $str[ $i ] == strtolower( $str[ $i ] ) ) ? strtoupper( $str[ $i ] ) : strtolower( $str[ $i ] );
    }
   
    return $ret;
}

function rand_case( $str ) {   
    for( $i = 0; $i < strlen( $str ); ++$i ) {
        $ret .= ( rand( 0, 1 ) == 0 ) ? strtolower( $str[ $i ] ) : strtoupper( $str[ $i ] );
    }
   
    return $ret;
}

function alter_case( $str ) {
    for( $i = 0; $i < strlen( $str ); ++$i ) {
        $ret .= ( $i % 2 == 0 ) ? strtoupper( $str[ $i ] ) : strtolower( $str[ $i ] );
    }
   
    return $ret;
}
?>

Examples:

<?php
# o RATO ROEU A ROUPA DO REI DE ROMA.
echo invert_case( 'O rato roeu a roupa do rei de roma.' );

# o RATo RoEU A ROUpA Do reI De rOma.
echo rand_case( 'O rato roeu a roupa do rei de roma.' );

# O RaTo rOeU A RoUpA Do rEi dE RoMa.
echo alter_case( 'O rato roeu a roupa do rei de roma.' );
?>

benshelock at gmail dot com (09-Apr-2009 09:51)

<?php
$a = str_shuffle('abcdefghijklmnopqrstuvwxyz1234567890');
echo substr($a,0,6);
?>
Creates a nice 6 digit unique ID similar to that of tinyurl.

merreborn at mailinator dot com (24-Jan-2008 07:46)

Re: jojersztajner at OXYGEN dot POLAND

"It may be useful if you want to create an accessible CAPTCHA."

This is a flawed concept, since:

1) It's not really accessible -- your scrambled text would produce incomprehensible output if passed through a screen reader (just imagine what a computer saying "uinervtisy" would sound like)

2) It's in no way secure.  A simple script with access to a copy of /usr/dict/words can reduce the space of possible solutions to no more than a handful.

i.e., it's trivial for a script to generate a command like the following, which solves the "uinervtisy" example 100% of the time:

php@server:~$ egrep -i '^u[inervts]{8}y$' /usr/share/dict/words
university
php@server:~$

Novel idea, but it would take a clever spammer all of 5 minutes to defeat it completely.

jojersztajner at OXYGEN dot POLAND (16-Jun-2007 11:27)

Aoccdrnig to rseearch at an Elingsh uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoatnt tihng is that the frist and lsat ltteer is at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit a porbelm. Tihs is bcuseae we do not raed ervey lteter by it slef but the wrod as a wlohe.

Hree's a cdoe taht slerbmcas txet in tihs way:
<?php
    function scramble_word($word) {
        if (strlen($word) < 2)
            return $word;
        else
            return $word{0} . str_shuffle(substr($word, 1, -1)) . $word{strlen($word) - 1};
    }

    echo preg_replace('/(\w+)/e', 'scramble_word("\1")', 'A quick brown fox jumped over the lazy dog.');
?>

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

CygnusX1 (14-Feb-2007 09:17)

To cobine functionality and simplicity of the two functions below we can have:

<?php
function generatePasswd($numAlpha=6,$numNonAlpha=2)
{
   $listAlpha = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
   $listNonAlpha = ',;:!?.$/*-+&@_+;./*&?$-!,';
   return str_shuffle(
      substr(str_shuffle($listAlpha),0,$numAlpha) .
      substr(str_shuffle($listNonAlpha),0,$numNonAlpha)
    );
}
?>

dzafel at op dot pl (29-Dec-2006 09:16)

Very, very simple random password generator, without using rand() function:

<?php
function random_password($chars = 8) {
   $letters = 'abcefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';
   return substr(str_shuffle($letters), 0, $chars);
}
?>

nmoyroud at teledetection dot fr (03-Nov-2005 12:38)

Just another update to password builder function. With this version, you can choose the number of alphanumeric characters to add and the number of non-alphanumeric characters. You obtain a more secure password. You can add another characters to the non-alphanumeric list if you need.
If you want a password with 8 alphanumeric and 3 non-alphanumeric characters in a random order, just call :
random_passwd(8,3);

function generatePasswd($numAlpha=6,$numNonAlpha=2) {
    $pwd = '';
    $listAlpha = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
    $listNonAlpha = ',;:!?.$/*-+&@_+;./*&?$-!,';

    $start = mt_rand(1, (strlen($listAlpha)-$numAlpha));
    $string = str_shuffle($listAlpha);
    $pwd .= substr($string,$start,$numAlpha);

    $start = mt_rand(1, (strlen($listNonAlpha)-$numNonAlpha));
    $string = str_shuffle($listNonAlpha);
    $pwd .= substr($string,$start,$numNonAlpha);

    return str_shuffle($pwd);
}

support at wiredlabs dot net (15-Aug-2005 10:03)

Just an update to sfalcon's function.  Chooses a random number within the length and then selects a random segment not the current segment of 1 to $numchar. Also added upper-case chars.

function random_passwd($numchar=8) {
    $str = "abcefghijklmnopqrstuvwxyz1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    $start = mt_rand(1, (strlen($str)-$numchar));
    $string = str_shuffle($str);
    $password = substr($string,$start,$numchar);
    return($password);
}

Qube, Efnet #php (05-Aug-2005 12:20)

(correction)
I balked at the loop method used below in inverting and randomising capitalisation and released that we just need to flip the bit (3rd bit or 6th depending on what way you look at it) and it would cause the case change in a character.

Full code and example:
http://www.pgregg.com/projects/php/code/str_case.php
(append an s to the url to get the .phps source)

I came up with a method and thanks to arpad (optimising as ever! :) we now have:

Invert case:
preg_replace('/[a-z]/ie', '\'$0\' ^ str_pad(\'\', strlen(\'$0\'), \' \')', $input);

Randomise case:
preg_replace('/[a-z]/ie', '(rand(0,1) ? \'$0\' ^ str_pad(\'\', strlen(\'$0\'), \' \') : \'$0\')', $input);

and for good measure:
Upper case:
preg_replace('/[a-z]/e', '\'$0\' & str_pad(\'\', strlen(\'$0\'), chr(223))', $input);

Lower case:
preg_replace('/[A-Z]/e', '\'$0\' | str_pad(\'\', strlen(\'$0\'), \' \')', $input);

rudigreen at gmail dot com (02-Jul-2005 03:20)

Here are 2 functions, one inverts the case of a string and the other one randomizes the captilization in a string, kinda
useful string operations.

<?

//Inverts the case of a string
function invert_case($str)
{
    $nstr = '';
    for($i=0;$i<strlen($str);$i++)
    {
        $char = substr($str,$i,1);
        //If it's lower case make it upper case
        if($char == strtolower($char))
        {
            $char = strtoupper($char);
        }
        else //if it's upper than make it lower
        {
            $char = strtolower($char);
        }
        $nstr .= $char;
    }
    return $nstr;
}

//Randomly capilizes/uncaptilizes chars in a string
function rand_case($str)
{
    $nstr = '';
    for($i=0;$i<strlen($str);$i++)
    {
        $char = substr($str,$i,1);
        $char = invert_case($char);
        //2 options, to change or not to change
        rand(0,1) == 1 ? $char = invert_case($char) : null;
        $nstr .= $char;
    }
    return $nstr;
}

//Example:
echo rand_case("pHp rooLz! gUyZ"); //produces something random
echo invert_case("pHP STRiNG sEx");//produces Php strIng SeX
?>

Michiel van den boogaard (17-Jan-2005 10:03)

Shortend function for PHP < 4.3
<?php 
function RandomPass($numchar) 
{ 
    $word = "a,b,c,d,e,f,g,h,i,j,k,l,m,1,2,3,4,5,6,7,8,9,0"; 
    $array=explode(",",$word); 
    shuffle($array); 
    $newstring = implode($array,""); 
    return substr($newstring, 0, $numchar); 
} 
?>

aidan at php dot net (26-Aug-2004 11:31)

This functionality is now implemented in the PEAR package PHP_Compat.

More information about using this function without upgrading your version of PHP can be found on the below link:

http://pear.php.net/package/PHP_Compat

sfalcon_(at)_pymesweb_(dot)_com (26-Aug-2004 04:28)

You can use str_shuffle to make simple and nice random passwords:

function random_passwd($numchar) {
      $string =str_shuffle("abcefghijklmnopqrstuvwxyz1234567890");
      $password = substr($string,1,$numchar);

      return($password);
}

echo random_passwd('8') // Will return something like "xa3dh214" =)