(PureBasic) Fetch Full Email Given Email Header

When email headers are fetched using UIDs (not sequence numbers), then the resultant email object (containing only the header) will include auto-generated ckx-imap-* header fields to record information about the uid, attachments, etc. The IMAP UID of the email will be available in the "ckx-imap-uid" header. There will also be a "ckx-imap-isUid" header field having the value "YES" or "NO". If the email header was downloaded by UID, then "ckx-imap-isUID" will contain the value "YES" and the value of the "ckx-imap-uid" header field is the IMAP UID. If the "ckx-imap-isUID" header has a value of "NO", then the "ckx-imap-uid" header field represents the sequence number. (Sequence numbers of emails on the server can change over time, depending on whether emails are deleted. UIDs must be used to ensure that the correct full email is downloaded.)

The Chilkat Email object provides a GetImapUid method to return the UID from the ckx-imap-uid header. This can then be used to download the full email using the FetchSingle method. Assuming the UID is known, download a single email by UID from an IMAP mail server.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkEmail.pb"
IncludeFile "CkImap.pb"

Procedure ChilkatExample()

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

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

    ; Connect to an IMAP server.
    ; Use TLS
    CkImap::setCkSsl(imap, 1)
    CkImap::setCkPort(imap, 993)
    success.i = CkImap::ckConnect(imap,"imap.someMailServer.com")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Login
    success = CkImap::ckLogin(imap,"***","***")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Select an IMAP mailbox
    success = CkImap::ckSelectMailbox(imap,"Inbox")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    emailHeader.i
    emailFull.i

    uid.i = 2014
    isUid.i = 1

    ; Fetch only the email header
    emailHeader = CkImap::ckFetchSingleHeader(imap,uid,isUid)
    If CkImap::ckLastMethodSuccess(imap) = 1

        ; Now fetch the full email
        uidFromCkxHeader.i = CkEmail::ckGetImapUid(emailHeader)
        If uidFromCkxHeader < 0
            ; Failed. 
            CkEmail::ckDispose(emailHeader)

            Debug "No ckx-imap-uid header was found."
            CkImap::ckDispose(imap)
            ProcedureReturn
        EndIf

        emailFull = CkImap::ckFetchSingle(imap,uidFromCkxHeader,1)
        If CkImap::ckLastMethodSuccess(imap) = 1

            ; OK, we have the full email, do whatever we want...

            CkEmail::ckDispose(emailFull)

        EndIf

        CkEmail::ckDispose(emailHeader)

    EndIf

    ; Disconnect from the IMAP server.
    success = CkImap::ckDisconnect(imap)


    CkImap::ckDispose(imap)


    ProcedureReturn
EndProcedure