(DataFlex) Download an IMAP Message Set

Demonstrates how to read a set of IMAP emails.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoImap
    Boolean iFetchUids
    Variant vMessageSet
    Handle hoMessageSet
    Variant vBundle
    Handle hoBundle
    Boolean iHeadersOnly
    Variant vEmail
    Handle hoEmail
    Integer i
    Integer iNumEmails
    String sTemp1
    Integer iTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatImap)) To hoImap
    If (Not(IsComObjectCreated(hoImap))) Begin
        Send CreateComObject of hoImap
    End

    // Connect using TLS.
    Set ComSsl Of hoImap To True
    Set ComPort Of hoImap To 993
    Get ComConnect Of hoImap "imap.example.com" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Authenticate
    Get ComLogin Of hoImap "email_account_login" "email_account_password" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Select an IMAP mailbox
    Get ComSelectMailbox Of hoImap "Inbox" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Search for messages with the word "test" in the subject.
    Move True To iFetchUids

    Get Create (RefClass(cComChilkatMessageSet)) To hoMessageSet
    If (Not(IsComObjectCreated(hoMessageSet))) Begin
        Send CreateComObject of hoMessageSet
    End
    Get pvComObject of hoMessageSet to vMessageSet
    Get ComQueryMbx Of hoImap "Subject test" iFetchUids vMessageSet To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Download the messages in a single call to FetchMsgSet.
    // 
    // This only makes sense if the number of emails to be downloaded is not too large.  
    // For example, you wouldn't want to download 10000 emails in a single call to FetchMsgSet.
    // Why? For two reasons:  (1) It could potentially cause an out-of-memory condition, and 
    // (2) it would take an extremely large amount of time.  The longer the amount of time,
    // the greater the likelihood of some kind of external networking or server problem occuring,
    // and if it happens, then you would need to re-download everything from the beginning again.
    // For large numbers of emails, it's better to loop over the emails in the message set
    // and download/process one at a time as shown here: Download IMAP Messages One at a Time
    // Downloading one message at a time makes it possible to resume the downloads rather than restart the entire operation all over again.

    // If the message set is reasonable in size, you can download all at once using FetchMsgSet:

    Get ComCount Of hoMessageSet To iTemp1
    Showln "Number of messages = " iTemp1

    Get Create (RefClass(cComChilkatEmailBundle)) To hoBundle
    If (Not(IsComObjectCreated(hoBundle))) Begin
        Send CreateComObject of hoBundle
    End
    Move False To iHeadersOnly
    Get pvComObject of hoMessageSet to vMessageSet
    Get pvComObject of hoBundle to vBundle
    Get ComFetchMsgSet Of hoImap iHeadersOnly vMessageSet vBundle To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Display the Subject and From of each email.
    Get Create (RefClass(cComChilkatEmail)) To hoEmail
    If (Not(IsComObjectCreated(hoEmail))) Begin
        Send CreateComObject of hoEmail
    End
    Move 0 To i
    Get ComMessageCount Of hoBundle To iNumEmails
    While (i < iNumEmails)
        Get pvComObject of hoEmail to vEmail
        Get ComEmailAt Of hoBundle i vEmail To iSuccess

        Get ComGetHeaderField Of hoEmail "Date" To sTemp1
        Showln sTemp1
        Get ComSubject Of hoEmail To sTemp1
        Showln sTemp1
        Get ComFrom Of hoEmail To sTemp1
        Showln sTemp1
        Showln "--"
        Move (i + 1) To i
    Loop



End_Procedure