Crypto.CryptoManager.DecryptAES C# (CSharp) Méthode

        public byte[] DecryptAES(byte[] cipheredPayload, CryptoLevel keysize = CryptoLevel.AES256)
        {
            // if the key strenght requested is different from the instance
            if (KeySize != KeySize)
            {
                KeySize = keysize;
                // re-calculate the decryption hash using the decryption level requested
                SetEncryptionLevel(KeySize);
            }

            // Check arguments.
            if (cipheredPayload == null || cipheredPayload.Length <= 0)
            {
                throw new ArgumentNullException("cipheredPayload");
            }
            if (key_array == null || key_array.Length <= 0)
            {
                throw new ArgumentNullException("Key");
            }
            if (iv_array == null || iv_array.Length <= 0)
            {
                throw new ArgumentNullException("Key");
            }

            // declare the output object.
            byte[] decrypted;

            // Create an Aes object
            // with the specified key and IV.
            using (Aes aes = Aes.Create())
            {
                aes.Key = key_array;
                aes.IV = iv_array;
                aes.Mode = CipherMode.CBC;
                aes.Padding = PaddingMode.PKCS7;

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

                // Create the streams used for decryption.
                using (MemoryStream msDecrypt = new MemoryStream(cipheredPayload))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        csDecrypt.Read(cipheredPayload, 0, cipheredPayload.Length);
                        csDecrypt.Flush();
                        decrypted = msDecrypt.ToArray();
                    }
                    msDecrypt.Close();
                }
            }
            return decrypted;
        }

    public static string SqlDecrypt(string json, int strength)
    {
        byte[] bson = Convert.FromBase64String(json);
        CryptoManager crypto = new CryptoManager();

        byte[] jbytes = crypto.DecryptAES(bson, (CryptoLevel)Convert.ToByte(strength));
        return Encoding.UTF8.GetString(jbytes);
    }