C# Encrypt Large files in a certain Folder

Question

I'm new to AES encryption in C# so excuse me if this question is a bit stupid. I'm using the current C# code to encrypt and decrypt large files, but I'm stuck figuring out a way to encrypt a lot of files in a certain folder, and then I want them moved into another directory once encrypted. Here's the code I've found in another StackOverflow post it works with encrypting large files very well but i couldn't figure out how to make it encrypt a lot of files in a certain directory and then move those encrypted files into another directory.

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

...

    // Rfc2898DeriveBytes constants:
    public readonly byte[] salt = new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; // Must be at least eight bytes.  MAKE THIS SALTIER!
    public const int iterations = 1042; // Recommendation is >= 1000.

    /// <summary>Decrypt a file.</summary>
    /// <remarks>NB: "Padding is invalid and cannot be removed." is the Universal CryptoServices error.  Make sure the password, salt and iterations are correct before getting nervous.</remarks>
    /// <param name="sourceFilename">The full path and name of the file to be decrypted.</param>
    /// <param name="destinationFilename">The full path and name of the file to be output.</param>
    /// <param name="password">The password for the decryption.</param>
    /// <param name="salt">The salt to be applied to the password.</param>
    /// <param name="iterations">The number of iterations Rfc2898DeriveBytes should use before generating the key and initialization vector for the decryption.</param>
    public void DecryptFile(string sourceFilename, string destinationFilename, string password, byte[] salt, int iterations)
    {
        AesManaged aes = new AesManaged();
        aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;
        aes.KeySize = aes.LegalKeySizes[0].MaxSize;
        // NB: Rfc2898DeriveBytes initialization and subsequent calls to   GetBytes   must be eactly the same, including order, on both the encryption and decryption sides.
        Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(password, salt, iterations);
        aes.Key = key.GetBytes(aes.KeySize / 8);
        aes.IV = key.GetBytes(aes.BlockSize / 8);
        aes.Mode = CipherMode.CBC;
        ICryptoTransform transform = aes.CreateDecryptor(aes.Key, aes.IV);

        using (FileStream destination = new FileStream(destinationFilename, FileMode.CreateNew, FileAccess.Write, FileShare.None))
        {
            using (CryptoStream cryptoStream = new CryptoStream(destination, transform, CryptoStreamMode.Write))
            {
                try
                {
                    using (FileStream source = new FileStream(sourceFilename, FileMode.Open, FileAccess.Read, FileShare.Read))
                    {
                        source.CopyTo(cryptoStream);
                    }
                }
                catch (CryptographicException exception)
                {
                    if (exception.Message == "Padding is invalid and cannot be removed.")
                        throw new ApplicationException("Universal Microsoft Cryptographic Exception (Not to be believed!)", exception);
                    else
                        throw;
                }
            }
        }
    }

    /// <summary>Encrypt a file.</summary>
    /// <param name="sourceFilename">The full path and name of the file to be encrypted.</param>
    /// <param name="destinationFilename">The full path and name of the file to be output.</param>
    /// <param name="password">The password for the encryption.</param>
    /// <param name="salt">The salt to be applied to the password.</param>
    /// <param name="iterations">The number of iterations Rfc2898DeriveBytes should use before generating the key and initialization vector for the decryption.</param>
    public void EncryptFile(string sourceFilename, string destinationFilename, string password, byte[] salt, int iterations)
    {
        AesManaged aes = new AesManaged();
        aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;
        aes.KeySize = aes.LegalKeySizes[0].MaxSize;
        // NB: Rfc2898DeriveBytes initialization and subsequent calls to   GetBytes   must be eactly the same, including order, on both the encryption and decryption sides.
        Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(password, salt, iterations);
        aes.Key = key.GetBytes(aes.KeySize / 8);
        aes.IV = key.GetBytes(aes.BlockSize / 8);
        aes.Mode = CipherMode.CBC;
        ICryptoTransform transform = aes.CreateEncryptor(aes.Key, aes.IV);

        using (FileStream destination = new FileStream(destinationFilename, FileMode.CreateNew, FileAccess.Write, FileShare.None))
        {
            using (CryptoStream cryptoStream = new CryptoStream(destination, transform, CryptoStreamMode.Write))
            {
                using (FileStream source = new FileStream(sourceFilename, FileMode.Open, FileAccess.Read, FileShare.Read))
                {
                    source.CopyTo(cryptoStream);
                }
            }
        }
    }

Answer 1

You can enumerate files in your directory:

foreach (var file in Directory.EnumerateFiles("DirectoryWithRawFilesPath")) { // using System.IO
  // Encrypt file

  File.Move(file, Path.Combine("DirectoryWithEncryptedFilesPath", file));
}