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PureBasic

Get the Content-ID of an Attachment

See more Email Object Examples

Demonstrates the Chilkat Email.GetAttachmentContentID method, which returns the Content-ID header field for the Nth attachment. The index is zero-based, so the first attachment is 0. This example adds an attachment and reads its Content-ID (which may be empty when none was assigned).

Background: A Content-ID is a unique identifier for a MIME part. It is essential for inline "related" resources, where HTML references an image by cid:, but ordinary file attachments usually have none. Reading it is useful when inspecting how a message is assembled, or when distinguishing parts that are referenced from the body versus those meant purely as downloadable attachments.

Chilkat PureBasic Downloads

PureBasic
IncludeFile "CkEmail.pb"

Procedure ChilkatExample()

    ;  Demonstrates the GetAttachmentContentID method, which returns the Content-ID header
    ;  field for the Nth attachment.  The index is zero-based (the first attachment is 0).

    email.i = CkEmail::ckCreate()
    If email.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkEmail::setCkSubject(email, "Attachment Content-ID")

    CkEmail::ckAddStringAttachment(email,"notes.txt","Some notes.")

    ;  Get the Content-ID of the first attachment (may be empty if none was assigned).
    cid.s = CkEmail::ckGetAttachmentContentID(email,0)
    Debug "Attachment 0 Content-ID: " + cid


    CkEmail::ckDispose(email)


    ProcedureReturn
EndProcedure