(DataFlex) Reading Unread POP3 Email

The POP3 protocol does not provide the ability to ask the server which emails are "unread". Furthermore, a pure POP3 server does not even keep this information. Some servers, such as Exchange Server, expose both POP3 and IMAP interfaces. In these cases, information about read/unread status exists on the server, but it is only available via the IMAP protocol. Email clients such as Outlook and Thunderbird keep read/unread information on the client computer. This example demonstrates how UIDLs can be saved to track and read "unread" email.

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

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Handle hoMailman
    Handle hoSaSeenUidls
    Boolean iSuccess
    Variant vSaUidls
    Handle hoSaUidls
    Variant vSaUnseenUidls
    Handle hoSaUnseenUidls
    Integer i
    Integer n
    Variant vBundle
    Handle hoBundle
    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.

    // The mailman object is used for receiving (POP3) 
    // and sending (SMTP) email.
    Get Create (RefClass(cComChilkatMailMan)) To hoMailman
    If (Not(IsComObjectCreated(hoMailman))) Begin
        Send CreateComObject of hoMailman
    End

    // Set the POP3 server's hostname
    Set ComMailHost Of hoMailman To "pop.someMailServer.com"

    // Set the POP3 login/password.
    Set ComPopUsername Of hoMailman To "***"
    Set ComPopPassword Of hoMailman To "***"

    // You may keep a list of already-seen UIDLs in a text file:
    // If this is the first time you're running this example,
    // create an empty text file named "seenUidls.txt"
    Get Create (RefClass(cComCkStringArray)) To hoSaSeenUidls
    If (Not(IsComObjectCreated(hoSaSeenUidls))) Begin
        Send CreateComObject of hoSaSeenUidls
    End
    Get ComLoadFromFile Of hoSaSeenUidls "seenUidls.txt" To iSuccess
    If (iSuccess <> True) Begin
        Showln "failed to load seenUidls.txt"
        Procedure_Return
    End

    // Get the complete list of UIDLs on the mail server.
    Get ComGetUidls Of hoMailman To vSaUidls
    If (IsComObject(vSaUidls)) Begin
        Get Create (RefClass(cComCkStringArray)) To hoSaUidls
        Set pvComObject Of hoSaUidls To vSaUidls
    End
    Get ComLastMethodSuccess Of hoMailman To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoMailman To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Create a new string array object (it's an object, not an actual array)
    // and add the UIDLs from saUidls that aren't already seen.
    Get Create (RefClass(cComCkStringArray)) To hoSaUnseenUidls
    If (Not(IsComObjectCreated(hoSaUnseenUidls))) Begin
        Send CreateComObject of hoSaUnseenUidls
    End

    Move 0 To i
    Get ComCount Of hoSaUidls To n
    While (i < n)
        Get ComContains Of hoSaSeenUidls (ComGetString(hoSaUidls, i)) To bTemp1
        If (bTemp1 <> True) Begin
            Get ComGetString Of hoSaUidls i To sTemp1
            Get ComAppend Of hoSaUnseenUidls sTemp1 To iSuccess
        End

        Move (i + 1) To i
    Loop

    Get ComCount Of hoSaUnseenUidls To iTemp1
    If (iTemp1 = 0) Begin
        Showln "No unseen emails!"
        Send Destroy of hoSaUidls
        Procedure_Return
    End

    // Download in full the unseen emails:
    Get pvComObject of hoSaUnseenUidls to vSaUnseenUidls
    Get ComFetchMultiple Of hoMailman vSaUnseenUidls 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
        Send Destroy of hoSaUidls
        Procedure_Return
    End

    Move 0 To i
    While (i < (ComMessageCount(hoBundle)))
        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 ComFrom Of hoEmail To sTemp1
        Showln sTemp1
        Get ComSubject Of hoEmail To sTemp1
        Showln sTemp1
        Showln "----"
        Send Destroy of hoEmail
        Move (i + 1) To i
    Loop

    // Save saUidls to "seenUidls.txt"
    Get ComSaveToFile Of hoSaUidls "seenUidls.txt" To iSuccess

    Send Destroy of hoSaUidls


End_Procedure