(PureBasic) How to Download Messages in MessageSet One at a Time

If a message set contains a huge number of emails, it's NOT a good idea to try to download all at once into an email bundle using a method such as FetchBundle. It's better to iterate over the messages in the set to download one by one.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkImap.pb"
IncludeFile "CkMessageSet.pb"
IncludeFile "CkEmail.pb"

Procedure ChilkatExample()

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

    imap.i = CkImap::ckCreate()
    If imap.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Connect using TLS.
    CkImap::setCkSsl(imap, 1)
    CkImap::setCkPort(imap, 993)
    success.i = CkImap::ckConnect(imap,"imap.example.com")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Authenticate
    success = CkImap::ckLogin(imap,"email_account_login","email_account_password")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Select an IMAP mailbox
    success = CkImap::ckSelectMailbox(imap,"Inbox")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Search for messages and return a set of matching messages.
    ; (This example will simply search for ALL messages.)
    fetchUids.i = 1
    messageSet.i = CkImap::ckSearch(imap,"ALL",fetchUids)
    If CkImap::ckLastMethodSuccess(imap) <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    Debug "Number of messages = " + Str(CkMessageSet::ckCount(messageSet))

    i.i = 0
    While i < CkMessageSet::ckCount(messageSet)
        email.i = CkImap::ckFetchSingle(imap,CkMessageSet::ckGetId(messageSet,i),fetchUids)
        If CkImap::ckLastMethodSuccess(imap) <> 1
            Debug CkImap::ckLastErrorText(imap)
            CkMessageSet::ckDispose(messageSet)

            CkImap::ckDispose(imap)
            ProcedureReturn
        EndIf

        Debug CkEmail::ckFrom(email) + "; " + CkEmail::ckSubject(email)
        CkEmail::ckDispose(email)

        i = i + 1
    Wend

    CkMessageSet::ckDispose(messageSet)

    Debug "OK"


    CkImap::ckDispose(imap)


    ProcedureReturn
EndProcedure