(VB.NET UWP/WinRT) Add Header Field to MIME Sub-Header in Email

Demonstrates how to add a header field to one of the attachment sub-headers in an email.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

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

Dim email As New Chilkat.Email

email.Subject = "test"
email.AddTo("Chilkat","support@chilkatsoft.com")
email.From = "Matt <matt@example.com>"
email.Body = "This is a simple plain-text body."

Dim success As Boolean = email.AddFileAttachment2("qa_data/1.HPM","application/x-hprimnet")
If (success <> True) Then
    Debug.WriteLine(email.LastErrorText)
    Exit Sub
End If


' Add a "ContentDescription: HPM/3.0" in the attachment's sub-header.
' The 1st attachment is at index 0.
email.AddAttachmentHeader(0,"Content-Description","HPM/3.0")

' Show the email MIME:
Debug.WriteLine(email.GetMime())

' This is the output:
' (Note: When Chilkat sends email, all CKX-* headers are removed prior to sending.)

' MIME-Version: 1.0
' Date: Wed, 16 Jan 2019 10:05:18 -0600
' Message-ID: <93B88835586270B7BE5202F84E171F29C10BA935@CHILKATSLICE>
' Content-Type: multipart/mixed; boundary="------------000502000000020502010608"
' X-Priority: 3 (Normal)
' Subject: test
' To: Chilkat <support@chilkatsoft.com>
' From: Matt <matt@example.com>
' CKX-Bounce-Address: matt@example.com
' 
' --------------000502000000020502010608
' Content-Type: text/plain; charset=us-ascii; format=flowed
' Content-Transfer-Encoding: 7bit
' 
' This is a simple plain-text body.
' --------------000502000000020502010608
' Content-Type: application/x-hprimnet; name="1.HPM"
' Content-Transfer-Encoding: base64
' Content-Disposition: attachment; filename="1.HPM"
' Content-Description: HPM/3.0
' 
' FILE_DATA_IS_HERE...
' 
' --------------000502000000020502010608--