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.NET Core C#

Send High Priority Email (SMTP, X-Priority header)

Demonstrates how to send high-priorty email (or lower priority email) by setting the X-Priority header field.

Chilkat .NET Core C# Downloads

.NET Core C#
bool success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// The mailman object is used for sending and receiving email.
Chilkat.MailMan mailman = new Chilkat.MailMan();

// Set the SMTP server (obviously, use your SMTP server, not chilkatsoft.com)
mailman.SmtpHost = "smtp.chilkatsoft.com";

// Set the SMTP login/password (if required)
mailman.SmtpUsername = "myUsername";
mailman.SmtpPassword = "myPassword";

// Create a new email object
Chilkat.Email email = new Chilkat.Email();

email.Subject = "This is a test";
email.Body = "This is a test";
email.From = "Chilkat Support <support@chilkatsoft.com>";
success = email.AddTo("Chilkat Admin","admin@chilkatsoft.com");
// To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

// To send high-priority email, 
// add the X-Priority header field with the value "1" 
// to indicate highest-priority.
// A value of "3" is normal, which is the same as not setting
// the X-Priority header at all, and "5" is the lowest. 
// "2" and "4" are in-betweens.

// Microsoft Outlook might add the following headers when
// sending high-priority email.

// X-Priority: 1 (Highest) 
// X-MSMail-Priority: High 
// Importance: High 

// The X-Priority header alone is enough to make the email high-priority.

email.AddHeaderField("X-Priority","1");

// Call SendEmail to connect to the SMTP server and send.
// The connection (i.e. session) to the SMTP server remains
// open so that subsequent SendEmail calls may use the
// same connection.  
success = mailman.SendEmail(email);
if (success != true) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

success = mailman.CloseSmtpConnection();
if (success != true) {
    Debug.WriteLine("Connection to SMTP server not closed cleanly.");
}

Debug.WriteLine("Mail Sent!");