OpenSSL 函数
PHP Manual

openssl_cipher_iv_length

(PHP 5 >= PHP 5.3.3, PHP 7)

openssl_cipher_iv_lengthGets the cipher iv length

说明

int openssl_cipher_iv_length ( string $method )

Gets the cipher initialization vector (iv) length.

参数

method

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

返回值

Returns the cipher length on success, or FALSE on failure.

错误/异常

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

范例

Example #1 openssl_cipher_iv_length() example

<?php
$method 
'AES-128-CBC';
$ivlen openssl_cipher_iv_length($method);

echo 
$ivlen;
?>

以上例程的输出类似于:

16

OpenSSL 函数
PHP Manual