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.NET Core C#

Create Non-Multipart Email with XML Body that is an Attachment

See more SMTP Examples

Creates an email where the only body is a binary WAV file. The technique used in the example could be applied to other binary files, such as PDF, MS-WORD docs, Excel docs, etc.

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 goal of this example is to create an email that has this MIME format,
// where the body of the email is XML using base64 encoding, 
// and the Content-Type and Content-Disposition are set as indicated.

// Date: Wed, 23 Aug 2023 09:01:52 +0200 (CEST)
// From: joe@example1.com
// Subject: [v=EMCS.NL][a=NL****][k=****][s=0]
// To: mary@example2.com
// MIME-Version: 1.0
// Content-Type: application/octet-stream; charset=us-ascii; name=6bd8dfe259b3a42c90a28a82b5fc6e77.txt
// Content-Transfer-Encoding: Base64
// Content-Disposition: attachment; filename=6bd8dfe259b3a42c90a28a82b5fc6e77.txt
// Message-Id: <......>
// 
// <multi-line base64 encoded XML here>

success = true;

string xmlBody = "<ie:IE801 xmlns:ie=\"urn:publicid:-:EC:DGTAXUD:EMCS:PHASE4:IE801:V3.01\" xmlns:tms=\"urn:publicid:-:EC:DGTAXUD:EMCS:PHASE4:TMS:V3.01\">....</ie:IE801>";

Chilkat.Email email = new Chilkat.Email();

// Add subject, TO, FROM, etc.
email.Subject = "[v=EMCS.NL][a=NL****][k=****][s=0]";
email.From = "joe@example1.com";
success = email.AddTo("Mary","mary@example2.com");

email.Body = xmlBody;

email.AddHeaderField("Content-Transfer-Encoding","Base64");
email.AddHeaderField("Content-Type","application/octet-stream; charset=us-ascii; name=6bd8dfe259b3a42c90a28a82b5fc6e77.txt");
email.AddHeaderField("Content-Disposition","attachment; filename=6bd8dfe259b3a42c90a28a82b5fc6e77.txt");

// Your email is ready to send
Chilkat.MailMan mailman = new Chilkat.MailMan();

mailman.SmtpHost = "smtp.my_mail_server.com";
mailman.SmtpUsername = "myUsername";
mailman.SmtpPassword = "myPassword";
mailman.SmtpPort = 465;
mailman.SmtpSsl = true;
mailman.StartTLS = true;

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!");