UWP: AES encryption and decryption

Question

I had a simple class to do some basic local encryption for Windows Phone 8. I wanted to use the class again in a new UWP Windows 10 app for the Windows Store. Unfortunately

Answer 1

Cleaner code

    public static async Task EncryptAesFileAsync(StorageFile fileForEncryption, string aesKey256, string iv16lenght)
    {

        bool success = false;
        try
        {
            //Initialize key
            IBuffer key = Convert.FromBase64String(aesKey256).AsBuffer();
            var m_iv = Convert.FromBase64String(iv16lenght).AsBuffer();
            SymmetricKeyAlgorithmProvider provider = SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithmNames.AesCbcPkcs7);
            var m_key = provider.CreateSymmetricKey(key);

            //secured data
            IBuffer data = await FileIO.ReadBufferAsync(fileForEncryption);
            IBuffer SecuredData = CryptographicEngine.Encrypt(m_key, data, m_iv);
            await FileIO.WriteBufferAsync(fileForEncryption, SecuredData);
            success = true;
        }
        catch (Exception ex)
        {
            success = false;
            DialogHelper.DisplayMessageDebug(ex);
        }
        return success;

    }
    public static async Task DecryptAesFileAsync(StorageFile EncryptedFile, string aesKey256, string iv16lenght)
    {

        bool success = false;
        try
        {
            //Initialize key
            IBuffer key = Convert.FromBase64String(aesKey256).AsBuffer();
            var m_iv = Convert.FromBase64String(iv16lenght).AsBuffer();
            SymmetricKeyAlgorithmProvider provider = SymmetricKeyAlgorithmProvider.OpenAlgorithm(SymmetricAlgorithmNames.AesCbcPkcs7);
            var m_key = provider.CreateSymmetricKey(key);

            //Unsecured Data
            IBuffer data = await FileIO.ReadBufferAsync(EncryptedFile);
            IBuffer UnSecuredData = CryptographicEngine.Decrypt(m_key, data, m_iv);
            await FileIO.WriteBufferAsync(EncryptedFile, UnSecuredData);
            success = true;
        }
        catch (Exception ex)
        {
            success = false;
            DialogHelper.DisplayMessageDebug(ex);
        }
        return success;

    }