c# - AES 実装の問題

Question

これが私のAES実装のコードです。文字列が渡されると、文字列を正常に暗号化します。しかし、上記の方法を使用して byte[] を文字列に変換しようとすると、エラーが発生します。同じように、復号化を実行しません。次に、コンソール ウィンドウで null を返すすべての値。画面上のエラーは次のとおりです。エラー: パディングが無効であり、削除できません。データベースに値を挿入しようとすると、このエラーが発生します。null値を取得しようとすると、戻り値が返されます。どうすればよいですか?

namespace AES_Implmentatio
{
class Program
{
    static void Main(string[] args) // write public in start
    {
        try
        {
            string original = "Here is some data to encrypt!";


            using (AesManaged myAes = new AesManaged())
            {
                //byte[] cipherbytes = System.Text.ASCIIEncoding.Default.GetBytes(encypted);
                //string result = Encoding.ASCII.GetString(encrypted);

                Console.WriteLine("Original:   {0}", original);
                byte[] encrypted = EncryptStringToBytes_Aes(original, myAes.Key, myAes.IV);
                string result1 = Encoding.ASCII.GetString(encrypted); // Not showing the results 
                Console.WriteLine("Encypted Data", result1);

                byte[] cipherbytes = System.Text.ASCIIEncoding.Default.GetBytes(result1);
                string roundtrip = DecryptStringFromBytes_Aes(cipherbytes, myAes.Key, myAes.IV);



            }

        }
        catch (Exception e)
        {
            Console.WriteLine("Error: {0}", e.Message);
        }
        Console.ReadLine();
    }
    static byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)
    {
        // Check arguments.
        if (plainText == null || plainText.Length <= 0)
            throw new ArgumentNullException("plainText");
        if (Key == null || Key.Length <= 0)
            throw new ArgumentNullException("Key");
        if (IV == null || IV.Length <= 0)
            throw new ArgumentNullException("IV");
        byte[] encrypted;
        // Create an AesManaged object
        // with the specified key and IV.
        using (AesManaged aesAlg = new AesManaged())
        {
            aesAlg.Key = Key;
            aesAlg.IV = IV;

            // Create a decrytor to perform the stream transform.
            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            // Create the streams used for encryption.
            using (MemoryStream msEncrypt = new MemoryStream())
            {
                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                    {

                        //Write all data to the stream.
                        swEncrypt.Write(plainText);
                    }
                    encrypted = msEncrypt.ToArray();
                }
            }
        }


        // Return the encrypted bytes from the memory stream.
        return encrypted;

    }

    static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)
    {
        // Check arguments.
        if (cipherText == null || cipherText.Length <= 0)
            throw new ArgumentNullException("cipherText");
        if (Key == null || Key.Length <= 0)
            throw new ArgumentNullException("Key");
        if (IV == null || IV.Length <= 0)
            throw new ArgumentNullException("IV");

        // Declare the string used to hold
        // the decrypted text.
        string plaintext = null;

        // Create an AesManaged object
        // with the specified key and IV.
        using (AesManaged aesAlg = new AesManaged())
        {
            aesAlg.Key = Key;
            aesAlg.IV = IV;

            // Create a decrytor to perform the stream transform.
            ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

            // Create the streams used for decryption.
            using (MemoryStream msDecrypt = new MemoryStream(cipherText))
            {
                using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                {
                    using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                    {

                        // Read the decrypted bytes from the decrypting stream
                        // and place them in a string.
                        plaintext = srDecrypt.ReadToEnd();
                    }
                }
            }

        }

        return plaintext;

    }
}
}