我有一个golang代码，它可以对给定的数据进行AES加密，并为它服务。
“地下室，开始"

func encrypt(key []byte, text string) string {

    plaintext := []byte(text)

    block, err := aes.NewCipher(key)
    if err != nil {
        panic(err)
    }

    ciphertext := make([]byte, aes.BlockSize+len(plaintext))
    iv := ciphertext[:aes.BlockSize]
    if _, err := io.ReadFull(rand.Reader, iv); err != nil {
        panic(err)
    }

    stream := cipher.NewCFBEncrypter(block, iv)
    stream.XORKeyStream(ciphertext[aes.BlockSize:], plaintext)

    return base64.URLEncoding.EncodeToString(ciphertext)
}

func decrypt(key []byte, cryptoText string) string {
    ciphertext, _ := base64.URLEncoding.DecodeString(cryptoText)

    block, err := aes.NewCipher(key)
    if err != nil {
        panic(err)
    }

    if len(ciphertext) < aes.BlockSize {
        panic("ciphertext too short")
    }
    iv := ciphertext[:aes.BlockSize]
    ciphertext = ciphertext[aes.BlockSize:]

    stream := cipher.NewCFBDecrypter(block, iv)
    stream.XORKeyStream(ciphertext, ciphertext)

    return string(ciphertext)
}

我需要在Flutter中处理相同的解密和加密。我尝试了下面的代码使用flutter加密包。

地穴镖

import 'package:encrypt/encrypt.dart';
String encryption(String plainText) {
     
     final key = Key.fromBase64(ENCRYPTION_KEY);
     final iv = IV.fromBase64(ENCRYPTION_IV);

     final encrypter = Encrypter(AES(key, mode: AESMode.cfb64, padding: null));
     final encrypted = encrypter.encrypt(plainText, iv: iv);

 return encrypted.base64;   
}

String decryption(String plainText) {

   final key = Key.fromBase64(ENCRYPTION_KEY);
   final iv = IV.fromBase64(ENCRYPTION_IV);

   final encrypter = Encrypter(AES(key, mode: AESMode.cfb64, padding: null));
   final decrypted = encrypter.decrypt(Encrypted.from64(plainText), iv: iv);

  return decrypted;   
 }

但我得到错误，并没有工作。我错过了什么？这是如何才能实现Flutter结束。
先谢了