(Unicode C) 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.

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#include <C_CkImapW.h>
#include <C_CkMessageSetW.h>
#include <C_CkEmailW.h>

void ChilkatSample(void)
    {
    HCkImapW imap;
    BOOL success;
    BOOL fetchUids;
    HCkMessageSetW messageSet;
    int i;
    HCkEmailW email;

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

    imap = CkImapW_Create();

    // Connect using TLS.
    CkImapW_putSsl(imap,TRUE);
    CkImapW_putPort(imap,993);
    success = CkImapW_Connect(imap,L"imap.example.com");
    if (success != TRUE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    // Authenticate
    success = CkImapW_Login(imap,L"email_account_login",L"email_account_password");
    if (success != TRUE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    // Select an IMAP mailbox
    success = CkImapW_SelectMailbox(imap,L"Inbox");
    if (success != TRUE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    // Search for messages and return a set of matching messages.
    // (This example will simply search for ALL messages.)
    fetchUids = TRUE;
    messageSet = CkImapW_Search(imap,L"ALL",fetchUids);
    if (CkImapW_getLastMethodSuccess(imap) != TRUE) {
        wprintf(L"%s\n",CkImapW_lastErrorText(imap));
        CkImapW_Dispose(imap);
        return;
    }

    wprintf(L"Number of messages = %d\n",CkMessageSetW_getCount(messageSet));

    i = 0;
    while (i < CkMessageSetW_getCount(messageSet)) {
        email = CkImapW_FetchSingle(imap,CkMessageSetW_GetId(messageSet,i),fetchUids);
        if (CkImapW_getLastMethodSuccess(imap) != TRUE) {
            wprintf(L"%s\n",CkImapW_lastErrorText(imap));
            CkMessageSetW_Dispose(messageSet);
            CkImapW_Dispose(imap);
            return;
        }

        wprintf(L"%s; %s\n",CkEmailW_ck_from(email),CkEmailW_subject(email));
        CkEmailW_Dispose(email);

        i = i + 1;
    }

    CkMessageSetW_Dispose(messageSet);

    wprintf(L"OK\n");


    CkImapW_Dispose(imap);

    }