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Tcl

Add a Custom Header to an Email Attachment

See more Email Object Examples

Demonstrates the Chilkat Email.AddAttachmentHeader method, which adds a custom MIME header field to an existing attachment identified by its zero-based index. This example adds an attachment (which becomes index 0), then attaches an extra header field to it and prints the resulting MIME.

Background: In MIME, every attachment is itself a mini-message with its own small block of headers — things like Content-Type, Content-Disposition, and Content-Transfer-Encoding that describe that specific part. AddAttachmentHeader lets you insert additional fields into that per-part header block, which is occasionally needed for interoperability with systems that look for custom X- headers or content identifiers on individual attachments.

Chilkat Tcl Downloads

Tcl

load ./chilkat.dll

#  Demonstrates the AddAttachmentHeader method, which adds a custom MIME header field to
#  an existing attachment, identified by its zero-based index.

set email [new_CkEmail]

CkEmail_put_Subject $email "Attachment with a custom header"
CkEmail_put_Body $email "The attachment has an extra MIME header."

#  Add an attachment; it becomes attachment index 0.
CkEmail_AddStringAttachment $email "data.txt" "Attachment body."

#  Add a custom header field to the first attachment (index 0).
CkEmail_AddAttachmentHeader $email 0 "X-Custom-Attachment-Header" "some value"

#  The custom header now appears in the attachment's MIME part.
puts [CkEmail_getMime $email]

delete_CkEmail $email