(DataFlex) Download IMAP Message Set using FetchBundle

Demonstrates how to read IMAP emails using the FetchBundle method.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoImap
    Boolean iSuccess
    Boolean iFetchUids
    Variant vMessageSet
    Handle hoMessageSet
    Variant vBundle
    Handle hoBundle
    Integer i
    Integer iNumEmails
    Variant vEmail
    Handle hoEmail
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    // 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 <> True) 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 <> True) 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 <> True) 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 ComSearch Of hoImap "Subject test" iFetchUids To vMessageSet
    If (IsComObject(vMessageSet)) Begin
        Get Create (RefClass(cComChilkatMessageSet)) To hoMessageSet
        Set pvComObject Of hoMessageSet To vMessageSet
    End
    Get ComLastMethodSuccess Of hoImap To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Download the messages in a single call to FetchBundle.
    // 
    // 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 FetchBundle.
    // 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 FetchBundle:

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

    Get ComFetchBundle Of hoImap vMessageSet To vBundle
    If (IsComObject(vBundle)) Begin
        Get Create (RefClass(cComChilkatEmailBundle)) To hoBundle
        Set pvComObject Of hoBundle To vBundle
    End
    Get ComLastMethodSuccess Of hoImap To bTemp1
    If (bTemp1 = False) Begin
        Send Destroy of hoMessageSet
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Display the Subject and From of each email.
    Move 0 To i
    Get ComMessageCount Of hoBundle To iNumEmails
    While (i < iNumEmails)
        Get ComGetEmail Of hoBundle i To vEmail
        If (IsComObject(vEmail)) Begin
            Get Create (RefClass(cComChilkatEmail)) To hoEmail
            Set pvComObject Of hoEmail To vEmail
        End

        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 "--"

        Send Destroy of hoEmail
        Move (i + 1) To i
    Loop

    Send Destroy of hoMessageSet
    Send Destroy of hoBundle


End_Procedure