Get Gmail labels for specified messages

Gmail treats labels as folders for the purposes of IMAP.

As such, labels can be modified using the standard IMAP commands, CreateFolder, RenameFolder, and DeleteFolder, that act on folders.

System labels, which are labels created by Gmail, are reserved and prefixed by “[Gmail]” or “[GoogleMail]” in the list of labels.

Use the XLIST command to get the entire list of labels for a mailbox.

The labels for a given message may be retrieved by using the X-GM-LABELS attribute with the FETCH command.

For list of messages

// C# version

using (Imap imap = new Imap())
{
    imap.ConnectSSL("imap.gmail.com");
    imap.UseBestLogin("pat@gmail.com", "password");

    imap.SelectInbox();

    List<long> uids = imap.GetAll();
    List<messageInfo> infos = imap.GetMessageInfoByUID(uids);

    foreach (MessageInfo info in infos)
    {
        List<string> labels = info.GmailLabels.Labels;

        Console.WriteLine("[{0}] {1}",
            string.Join(" ", labels.ToArray()),
            info.Envelope.Subject);
    }

    imap.Close();
}

' VB.NET version

Using imap As New Imap()
	imap.ConnectSSL("imap.gmail.com")
	imap.UseBestLogin("pat@gmail.com", "password")

	imap.SelectInbox()

	Dim uids As List(Of Long) = imap.GetAll()
	Dim infos As List(Of MessageInfo) = imap.GetMessageInfoByUID(uids)

	For Each info As MessageInfo In infos
            Dim labels As List(Of String) = info.GmailLabels.Labels

	    Console.WriteLine("[{0}] {1}",  _
                String.Join(" ", labels.ToArray()),  _
                info.Envelope.Subject)
	Next

	imap.Close()
End Using

For single message:

// C# version

using (Imap imap = new Imap())
{
    imap.ConnectSSL("imap.gmail.com");
    imap.Login("pat@gmail.com", "password");

    imap.SelectInbox();

    long uid = imap.GetAll().Last();
    List<string> labels = imap.GmailGetLabelsByUID(uid);

    labels.ForEach(Console.WriteLine);

    imap.Close();
}

' VB.NET version

Using imap As New Imap()
	imap.ConnectSSL("imap.gmail.com")
	imap.Login("pat@gmail.com", "password")

	imap.SelectInbox()

	Dim uid As Long = imap.GetAll().Last()
	Dim labels As List(Of String) = imap.GmailGetLabelsByUID(uid)

	labels.ForEach(Console.WriteLine)

	imap.Close()
End Using

You can learn more about this Gmail IMAP extension here:
http://code.google.com/apis/gmail/imap/#x-gm-labels

Tags: C# Gmail IMAP IMAP component VB.NET X-GM-LABELS