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VB.NET

Auto-Generate or Explicitly Specify the Message-ID Email Header

Demonstrates how to auto-generate or explicitly specify the Message-ID header field.

Chilkat VB.NET Downloads

VB.NET
Dim success As Boolean = False

Dim email As New Chilkat.Email

email.Subject = "test"
email.Body = "test"
email.AddTo("Joe","joe@example1.com")
email.From = "mary@example2.com"

Dim mailman As New Chilkat.MailMan

' When the mailman sends email, it renders the email to be sent,
' and then sends the rendered MIME.

' Instead of actually sending the email, this example will render
' to MIME so we can see what would be sent..

' We can explicitly set the Message-ID like this:
mailman.AutoGenMessageId = False
email.AddHeaderField("Message-ID","<xyz123@abc>")

Dim mimeStr As String = mailman.RenderToMime(email)
Debug.WriteLine(mimeStr)

' This is what we get:

' MIME-Version: 1.0
' Date: Mon, 20 Jul 2020 17:20:09 -0500
' Message-ID: <xyz123@abc>
' Content-Type: text/plain; charset=us-ascii; format=flowed
' Content-Transfer-Encoding: 7bit
' X-Priority: 3 (Normal)
' Subject: test
' To: Joe <joe@example1.com>
' From: mary@example2.com
' 
' test

Debug.WriteLine("--------")

' If we auto-generate...
mailman.AutoGenMessageId = True
mimeStr = mailman.RenderToMime(email)
Debug.WriteLine(mimeStr)

' We get this:

' MIME-Version: 1.0
' Date: Mon, 20 Jul 2020 17:21:20 -0500
' Message-ID: <04EDE096BBFE484967F6398A973B0FCF6EA09A44@CHILKATSLICE>
' Content-Type: text/plain; charset=us-ascii; format=flowed
' Content-Transfer-Encoding: 7bit
' X-Priority: 3 (Normal)
' Subject: test
' To: Joe <joe@example1.com>
' From: mary@example2.com
' 
' test