(PHP 7, PHP 8)
random_bytes — Get cryptographically secure random bytes
Generates a string containing uniformly selected random bytes with the requested length.
As the returned bytes are selected completely randomly, the resulting string is likely to contain unprintable characters or invalid UTF-8 sequences. It may be necessary to encode it before transmission or display.
The randomness generated by this function is suitable for all applications, including the generation of long-term secrets, such as encryption keys.
Las fuentes de aleatoriedad empleadas por esta función son las siguientes:
Nota: Aunque esta función se añadió a PHP en PHP 7.0, hay disponible una » implementación de espacio de usuario para PHP 5.2 hasta 5.6, inclusive.
length
The length of the random string that should be returned in bytes; must be 1 or greater.
A string containing the requested number of cryptographically secure random bytes.
length is less than 1,
a ValueError will be thrown.
| Versión | Descripción |
|---|---|
| 8.2.0 | In case of a CSPRNG failure, this function will now throw a Random\RandomException. Previously a plain Exception was thrown. |
Ejemplo #1 random_bytes() example
<?php
$bytes = random_bytes(5);
var_dump(bin2hex($bytes));
?>El resultado del ejemplo sería algo similar a:
string(10) "385e33f741"