(DataFlex) POP3: Download Most Recent Email (method 1)

How to ready the N most recent email from a POP3 server.

The POP3 protocol does not provide the ability to request the most recent email, nor does it provide the ability to download email based on read/unread status or any other criteria. The design principle behind POP3 is that it is a temporary holding store for incoming email and email clients or other applications will transfer email from the POP3 server to a local persistent store where it will be managed. Therefore, POP3 does not provide sophisticated functionality (as opposed to IMAP which has the opposite design philosophy: that email is maintained and organized on the server).

This example shows one possible way to retrieve the N most recent emails from a POP3 server. It downloads the headers into a bundle object, then sorts the bundle by date, and finally retrieves the most recent emails by UIDL.

Another alternative is to download the UIDL list and then assume that the 1st N UIDLs are the most recent.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoMailman
    Boolean iSuccess
    Variant vBundle
    Handle hoBundle
    Boolean iAscending
    Variant vSaUidls
    Handle hoSaUidls
    Integer n
    Integer i
    Variant vEmail
    Handle hoEmail
    Variant vBundle2
    Handle hoBundle2
    String sTemp1
    Boolean bTemp1

    // This example assumes 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 "myLogin"
    Set ComPopPassword Of hoMailman To "myPassword"

    // Read mail headers and one line of the body.
    Get ComGetAllHeaders Of hoMailman 1 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

    // Sort the bundle by date
    Move False To iAscending
    Send ComSortByDate To hoBundle iAscending

    // Get the 10 most recent UIDLs
    Get Create (RefClass(cComCkStringArray)) To hoSaUidls
    If (Not(IsComObjectCreated(hoSaUidls))) Begin
        Send CreateComObject of hoSaUidls
    End
    Get ComMessageCount Of hoBundle To n
    If (n > 10) Begin
        Move 10 To n
    End

    Move 0 To i

    While (i < n)
        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 ComUidl Of hoEmail To sTemp1
        Get ComAppend Of hoSaUidls sTemp1 To iSuccess
        Send Destroy of hoEmail

        Move (i + 1) To i
    Loop

    Send Destroy of hoBundle

    // Download in full the 10 most recent emails:
    Get pvComObject of hoSaUidls to vSaUidls
    Get ComFetchMultiple Of hoMailman vSaUidls To vBundle2
    If (IsComObject(vBundle2)) Begin
        Get Create (RefClass(cComChilkatEmailBundle)) To hoBundle2
        Set pvComObject Of hoBundle2 To vBundle2
    End
    Get ComLastMethodSuccess Of hoMailman To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoMailman To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Move 0 To i
    While (i < (ComMessageCount(hoBundle2)))
        Get ComGetEmail Of hoBundle2 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



End_Procedure