Dutch PHP Conference 2025 - Call For Papers

Random\Randomizer::getBytesFromString

(PHP 8 >= 8.3.0)

Random\Randomizer::getBytesFromStringGet random bytes from a source string

Опис

public Random\Randomizer::getBytesFromString(string $string, int $length): string

Generates a string containing uniformly selected random bytes from the input string with the requested length.

The chance for a byte to be selected is proportional to its share of the input string. If each byte occurs the same amount of times, each byte is equally likely to be selected.

Параметри

string

The string from which the returned bytes are selected.

length

The length of the random string that should be returned in bytes; must be 1 or greater.

Значення, що повертаються

A string containing the requested number of random bytes taken from the input string.

Помилки/виключення

Приклади

Приклад #1 Random\Randomizer::getBytesFromString() example

<?php
$randomizer
= new \Random\Randomizer();

printf(
"%s.example.com",
$randomizer->getBytesFromString('abcdefghijklmnopqrstuvwxyz0123456789', 16)
);
?>

Поданий вище приклад виведе щось схоже на:

3zsw04eiubcf82jd.example.com

Приклад #2 Generate a random code for multi-factor authentication

<?php
// The Secure engine is the default, but we make it explicit, because
// multi-factor codes are security sensitive.
$randomizer = new \Random\Randomizer(new \Random\Engine\Secure());

echo
implode('-', str_split($randomizer->getBytesFromString('0123456789', 20), 5));
?>

Поданий вище приклад виведе щось схоже на:

11551-80418-27047-42075

Приклад #3 Select from a string with a non-uniform distribution

<?php
$randomizer
= new \Random\Randomizer();

echo
$randomizer->getBytesFromString('aaaaabcdef', 20);
?>

Поданий вище приклад виведе щось схоже на:

fddacbeaaeaaacaaaaca

Прогляньте також

add a note

User Contributed Notes

There are no user contributed notes for this page.
To Top