Running a class with arguments

Hi i'm trying to run a class when a checkbox is checked but i get errors asking for arguments to be added i have tried with the following code but still no luck!

 private void Encrypt_Click(object sender, RoutedEventArgs e)
    {
       if (UseAES.IsChecked == true)
           AesEncryptText(input, password);            
    }

This is the class its calling

  public string AesEncryptText(string input, string password)
    {


        byte[] bytesToBeEncrypted = Encoding.UTF8.GetBytes(input);
        byte[] passwordBytes = Encoding.UTF8.GetBytes(password);


        passwordBytes = SHA256.Create().ComputeHash(passwordBytes);

        byte[] bytesEncrypted = AES_Encrypt(bytesToBeEncrypted, passwordBytes);

        string result = Convert.ToBase64String(bytesEncrypted);

        DecryptText.Text = result;

        return result;
    }