public static void DecryptFile(string encryptedFilePath, byte[] key, byte[] iv)
        {
            using (var aes = Aes.Create())
            {
                aes.KeySize = KeySize;
                aes.BlockSize = BlockSize;
                aes.Key = key;
                aes.IV = iv;

                using (var encryptedFileStream = new FileStream(encryptedFilePath, FileMode.Open, FileAccess.Read))
                using (var decryptedFileStream = new FileStream(encryptedFilePath.Replace(".enc", ""), FileMode.Create, FileAccess.Write))
                using (var cryptoStream = new CryptoStream(encryptedFileStream, aes.CreateDecryptor(), CryptoStreamMode.Read))
                {
                    cryptoStream.CopyTo(decryptedFileStream);
                }
            }
            File.Delete(encryptedFilePath);
        }