AES-256-CBC encryption?

[Justa Lol]

i have in php two functions, one to encrypt and one to decrypt.

function Encrypt($message) {
$Method = "AES-256-CBC";
$passPhrase = "key";
$iVector = 1234567890123456;
$encryptedMessage = openssl_encrypt($message, $Method, $passPhrase, $iVector);
return $encryptedMessage;
}
function Decrypt($message) {
$Method = "AES-256-CBC";
$passPhrase = "key";
$iVector = 1234567890123456;
$decryptedMessage = openssl_decrypt($message, $Method, $passPhrase, $iVector);
return $decryptedMessage;
} 

what i want to do, is encrypt a message, using the same method in vb.net as i do in php, how would i go about doing this?