(DataFlex) Process Large POP3 Mailbox

Demonstrates how to read email from a mailbox that may contain a large number of emails.

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

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Handle hoMailman
    Variant vSa
    Handle hoSa
    Integer i
    Integer iNumEmails
    Integer iChunkSize
    Integer iChunkBeginIdx
    Integer iChunkEndIdx
    Variant vSaChunk
    Handle hoSaChunk
    Boolean iSuccess
    String sChunkStr
    Variant vBundle
    Handle hoBundle
    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(cComChilkatMailMan)) To hoMailman
    If (Not(IsComObjectCreated(hoMailman))) Begin
        Send CreateComObject of hoMailman
    End

    Set ComMailHost Of hoMailman To "pop.example.com"

    Set ComPopUsername Of hoMailman To "myLogin"
    Set ComPopPassword Of hoMailman To "myPassword"

    Set ComMailPort Of hoMailman To 995
    Set ComPopSsl Of hoMailman To True

    // Get the list of UIDLs for all emails in the mailbox.
    Get ComGetUidls Of hoMailman To vSa
    If (IsComObject(vSa)) Begin
        Get Create (RefClass(cComCkStringArray)) To hoSa
        Set pvComObject Of hoSa To vSa
    End
    Get ComLastMethodSuccess Of hoMailman To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoMailman To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComCount Of hoSa To iNumEmails
    If (iNumEmails = 0) Begin
        Showln "Mailbox is empty"
        Procedure_Return
    End

    Move 6 To iChunkSize

    // Download the emails in chunks of 6 emails each.
    Move 0 To iChunkBeginIdx
    Move (iChunkSize - 1) To iChunkEndIdx
    If (iChunkEndIdx >= iNumEmails) Begin
        Move (iNumEmails - 1) To iChunkEndIdx
    End

    Get Create (RefClass(cComCkStringArray)) To hoSaChunk
    If (Not(IsComObjectCreated(hoSaChunk))) Begin
        Send CreateComObject of hoSaChunk
    End
    While (iChunkBeginIdx < iNumEmails)

        Showln iChunkBeginIdx " to " iChunkEndIdx

        // Build a chunk of UIDLs.
        Send ComClear To hoSaChunk
        For i From iChunkBeginIdx To iChunkEndIdx
            Get ComGetString Of hoSa i To sTemp1
            Get ComAppend Of hoSaChunk sTemp1 To iSuccess
        Loop

        // Log the UIDLs in this chunk...
        Get ComSaveToText Of hoSaChunk To sChunkStr
        Showln sChunkStr

        // Download this chunk of email from the POP3 server.
        Get pvComObject of hoSaChunk to vSaChunk
        Get ComFetchMultiple Of hoMailman vSaChunk To vBundle
        If (IsComObject(vBundle)) Begin
            Get Create (RefClass(cComChilkatEmailBundle)) To hoBundle
            Set pvComObject Of hoBundle To vBundle
        End
        Get ComLastMethodSuccess Of hoMailman To bTemp1
        If (bTemp1 = False) Begin
            Get ComLastErrorText Of hoMailman To sTemp1
            Showln sTemp1
            Procedure_Return
        End

        Get ComMessageCount Of hoBundle To iTemp1
        Showln "Downloaded " iTemp1 " emails."
        Showln "----"

        // Process the bundle...
        // (your application's processing code goes here...)

        Send Destroy of hoBundle

        // Get the next chunk...
        Move (iChunkBeginIdx + iChunkSize) To iChunkBeginIdx
        Move (iChunkEndIdx + iChunkSize) To iChunkEndIdx
        If (iChunkEndIdx >= iNumEmails) Begin
            Move (iNumEmails - 1) To iChunkEndIdx
        End

    Loop

    Send Destroy of hoSa


End_Procedure