private void btnSendWinnersMail_Click(object sender, RoutedEventArgs e)
        {
            Deelnemer winnaar = (Deelnemer)lstMailingList.SelectedValue;

            string rapport = beheerWinaars.OpmaakEmail(winnaar);

            rapport += txtWinnersMail.Text;
            string from, to, subject, paswoord;

            from     = "*****@*****.**";
            to       = winnaar.Email;
            subject  = "Gefeliciteerd!";
            paswoord = "Huiswerk104";

            MailingComponents mailWinnaar = new MailingComponents(from, to, subject, rapport, from, paswoord);

            if (!SendMail.SendMessage(mailWinnaar))
            {
                MessageBox.Show("De e-mail is niet verzonden");
            }
            else
            {
                MessageBox.Show("De e-mail is verzonden");
            }
            txtWinnersMail.Clear();
            MaakVeldenDeelnemersLeeg();
            DataOphalen();
        }
        private void btnSendNewsLetter_Click(object sender, RoutedEventArgs e)
        {
            foreach (Deelnemer mailDeelnemer in beheerDeelnemers.deelnemers)
            {
                string rapport = beheerWinaars.OpmaakEmail(mailDeelnemer);
                rapport += txtNewsLetter.Text;
                string from, to, subject, paswoord;
                from     = "*****@*****.**";
                to       = mailDeelnemer.Email;
                subject  = "Newsletter";
                paswoord = "Huiswerk104";

                MailingComponents _mailDeelnemer = new MailingComponents(from, to, subject, rapport, from, paswoord);

                if (!SendMail.SendMessage(_mailDeelnemer))
                {
                    MessageBox.Show($"De e-mail is niet verzonden {_mailDeelnemer.To}");
                }
            }
            txtNewsLetter.Clear();
            MessageBox.Show("De e-mails zijn verzonden!");
        }
        public static bool SendMessage(MailingComponents mailingComponents)
        {
            bool mailSent = false;

            MailAddress from = new MailAddress(mailingComponents.From);

            MailAddress to      = new MailAddress(mailingComponents.To);
            MailMessage message = new MailMessage(from, to);

            message.IsBodyHtml = true;
            message.Subject    = mailingComponents.Subject;
            if (!String.IsNullOrEmpty(mailingComponents.Cc))
            {
                message.CC.Add(mailingComponents.Cc);
            }
            if (!String.IsNullOrEmpty(mailingComponents.Bcc))
            {
                message.CC.Add(mailingComponents.Bcc);
            }
            message.Body    = mailingComponents.HtmlBody;
            message.Subject = mailingComponents.Subject;
            SmtpClient client = new SmtpClient(mailingComponents.SmtpServer);

            try
            {
                client.Port        = mailingComponents.Port;
                client.Credentials = new System.Net.NetworkCredential(mailingComponents.From, mailingComponents.PassWord);
                client.EnableSsl   = true;

                client.Send(message);
                mailSent = true;
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught in CreateTestMessage(): {0}",
                                  ex.ToString());
            }
            return(mailSent);
        }