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openssl_cipher_key_length

(PHP 8 >= 8.2.0)

openssl_cipher_key_length — Gets the cipher key length

说明

openssl_cipher_key_length(string $cipher_algo): int|false

Gets the cipher key length.

参数

cipher_algo: The cipher method, see openssl_get_cipher_methods() for a list of potential values.

返回值

Returns the cipher length on success, 或者在失败时返回 false.

错误／异常

Emits an E_WARNING level error when the cipher algorithm is unknown.

示例

示例 #1 openssl_cipher_key_length() example

<?php
$method = 'AES-128-CBC';

var_dump(openssl_cipher_key_length($method));
?>

以上示例的输出类似于：

int(16)