mail.Headers.Add("expiry-date", sTime);
e.g.
namespace RedmineMailService
{
// https://stackoverflow.com/questions/637866/sending-mail-without-installing-an-smtp-server
// http://www.nullskull.com/articles/20030316.asp
// https://www.redmine.org/boards/2/topics/26198
// https://www.redmine.org/boards/2/topics/22259
static class MailSender
{
public static void Test()
{
using (System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient())
{
using (System.Net.Mail.MailMessage mail = new System.Net.Mail.MailMessage())
{
client.Port = 25;
client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
// client.UseDefaultCredentials = true;
// Must be after UseDefaultCredentials
// client.Credentials = new System.Net.NetworkCredential("mailboxname", "password", "example.com");
// client.Port = 587;
// client.EnableSsl = true;
client.Host = "COR-EXCHANGE.cor.local";
mail.Subject = "this is a test email.";
mail.Body = "Test";
// https://www.iana.org/assignments/message-headers/message-headers.xhtml
// https://tools.ietf.org/html/rfc4021#page-32
// mail.Headers.Add("Importance", "High"); // High, normal, or low.
mail.Priority = System.Net.Mail.MailPriority.High;
// for read-receipt
mail.Headers.Add("Disposition-Notification-To", RedmineMailService.Trash.UserData.info);
string sTime = System.DateTime.UtcNow.AddDays(-1).ToString("dd MMM yyyy", System.Globalization.CultureInfo.InvariantCulture) + " " +
System.DateTime.UtcNow.ToShortTimeString() + " +0000"; // Fixed, from +0100 - just take UTC - works in .NET 2.0 - no need for offset
// Set a message expiration date
// When the expiration date passes, the message remains visible
// in the message list with a strikethrough.
// It can still be opened, but the strikethrough gives a visual clue
// that the message is out of date or no longer relevant.
mail.Headers.Add("expiry-date", sTime);
// https://tools.ietf.org/html/rfc2076#page-16
// https://tools.ietf.org/html/rfc1911
// The case-insensitive values are "Personal" and "Private"
// Normal, Confidential,
// If a sensitivity header is present in the message, a conformant
// system MUST prohibit the recipient from forwarding this message to
// any other user. If the receiving system does not support privacy and
// the sensitivity is one of "Personal" or "Private", the message MUST
// be returned to the sender with an appropriate error code indicating
// that privacy could not be assured and that the message was not
// delivered [X400].
mail.Headers.Add("Sensitivity", "Company-confidential");
// for delivery receipt
mail.DeliveryNotificationOptions =
System.Net.Mail.DeliveryNotificationOptions.OnSuccess
| System.Net.Mail.DeliveryNotificationOptions.OnFailure;
// mail.From = new System.Net.Mail.MailAddress("somebody@friends.com", "SomeBody");
mail.From = new System.Net.Mail.MailAddress(RedmineMailService.Trash.UserData.info, "COR ServiceDesk");
mail.To.Add(new System.Net.Mail.MailAddress(RedmineMailService.Trash.UserData.Email, "A"));
// mail.To.Add(new System.Net.Mail.MailAddress("user1@friends.com", "B"));
// mail.To.Add(new System.Net.Mail.MailAddress("user2@friends.com", "B"));
// mail.To.Add(new System.Net.Mail.MailAddress(RedmineMailService.Trash.UserData.info, "ServiceDesk"));
try
{
System.Console.WriteLine("Host: " + client.Host);
System.Console.WriteLine("Credentials: " + System.Convert.ToString(client.Credentials));
client.Send(mail);
System.Console.WriteLine("Mail versendet");
}
catch (System.Exception ex)
{
do
{
System.Console.Write("Fehler: ");
System.Console.WriteLine(ex.Message);
System.Console.WriteLine("Stacktrace: ");
System.Console.WriteLine(ex.StackTrace);
System.Console.WriteLine(System.Environment.NewLine);
ex = ex.InnerException;
} while (ex != null);
} // End Catch
} // End Using mail
} // End Using client
} // End Sub Test
} // End Class MailSender
} // End Namespace RedmineMailService.Trash
