Generates cryptographically secure pseudo-random bytes

Açıklama

string random_bytes ( int $length )

Generates an arbitrary length string of cryptographic random bytes that are suitable for cryptographic use, such as when generating salts, keys or initialization vectors.

The sources of randomness used for this function are as follows:

On Windows, » CryptGenRandom() will always be used.
On Linux, the » getrandom(2) syscall will be used if available.
On other platforms, /dev/urandom will be used.
If none of the aforementioned sources are available, then an Exception will be thrown.

Bilginize: Although this function was added to PHP in PHP 7.0, a » userland implementation is available for PHP 5.2 to 5.6, inclusive.

Değiştirgeler

length: The length of the random string that should be returned in bytes.

Dönen Değerler

Returns a string containing the requested number of cryptographically secure random bytes.

Hatalar/İstisnalar

If an appropriate source of randomness cannot be found, an Exception will be thrown.
If invalid parameters are given, a TypeError will be thrown.
If an invalid length of bytes is given, an Error will be thrown.

Örnekler

Örnek 1 random_bytes() example


<?php
$bytes = random_bytes(5);
var_dump(bin2hex($bytes));
?>

Yukarıdaki örnek şuna benzer bir çıktı üretir:

string(10) "385e33f741"

Ayrıca Bakınız

random_int() - Generates cryptographically secure pseudo-random integers
openssl_random_pseudo_bytes() - Yarı-rasgele dizge üretir
bin2hex() - Bir ikil verinin onaltılık gösterimini elde eder