(C# UWP/WinRT) 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 interate over the message numbers in the set to download one by one.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

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

// This example copies an email from one mailbox to another.
Chilkat.Imap imap = new Chilkat.Imap();

// Connect using TLS.
imap.Ssl = true;
imap.Port = 993;
bool success = await imap.ConnectAsync("imap.example.com");
if (success != true) {
    Debug.WriteLine(imap.LastErrorText);
    return;
}

// Authenticate
success = await imap.LoginAsync("email_account_login","email_account_password");
if (success != true) {
    Debug.WriteLine(imap.LastErrorText);
    return;
}

// Select an IMAP mailbox
success = await imap.SelectMailboxAsync("Inbox");
if (success != true) {
    Debug.WriteLine(imap.LastErrorText);
    return;
}

// Search for messages having "Test email" in the subject.
bool fetchUids = true;
Chilkat.MessageSet messageSet = await imap.SearchAsync("ALL",fetchUids);
if (imap.LastMethodSuccess != true) {
    Debug.WriteLine(imap.LastErrorText);
    return;
}

Debug.WriteLine("Number of messages = " + Convert.ToString(messageSet.Count));

int i = 0;
while (i < messageSet.Count) {
    Chilkat.Email email = await imap.FetchSingleAsync(messageSet.GetId(i),fetchUids);
    if (imap.LastMethodSuccess != true) {
        Debug.WriteLine(imap.LastErrorText);

        return;
    }

    Debug.WriteLine(email.From + "; " + email.Subject);

    i = i + 1;
}

Debug.WriteLine("OK");