Working with ImapClient Asynchronously

Working with messages can be performed asynchronously by using the Aspose.Email’s ImapClient. This article shows retrieving messages from a mailbox asynchronously. This article also shows how to list messages by providing search criteria using MailQuery. It will be shown separately how to interrupt an operation with email messages started by a task-based asynchronous pattern (TAP) method.

Retrieve Messages Asynchronously

The following code snippet shows you how to retrieve messages asynchronously.

List Messages Asynchronously with MailQuery

The MailQuery class can be used to specify search criteria for retrieving a specified list of messages asynchronously as is shown in the following code sample.

How to Interrupt a TAP Method

Starting with .NET Framework 4.5, you can use asynchronous methods implemented according to TAP model. The code snippet below shows how to append many messages using the task-based asynchronous pattern method named AppendMessagesAsync and then interrupt this process after a while.

// For complete examples and data files, please go to https://github.com/aspose-email/Aspose.Email-for-.NET

List<MailMessage> mailMessages = new List<MailMessage>();

// create mail messages
for (int i = 0; i < 100; i++)
    mailMessages.Add(new MailMessage(senderEmail, receiverEmail, $"Message #{i}", "Text"));

using (ImapClient client = new ImapClient(host, 993, senderEmail, password, SecurityOptions.SSLImplicit))
{
    CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
    AutoResetEvent autoResetEvent = new AutoResetEvent(false);
    Exception exception = null;

    ThreadPool.QueueUserWorkItem(delegate
    {
        try
        {
            // start uploading the messages
            var task = client.AppendMessagesAsync(mailMessages, cancellationTokenSource.Token);
            AppendMessagesResult appendMessagesResult = task.GetAwaiter().GetResult();
            Console.WriteLine("All messages have been appended.");
        }
        catch (Exception e)
        {
            exception = e;
        }
        finally
        {
            autoResetEvent.Set();
        }
    });

    Thread.Sleep(5000);

    // stop uploading the messages
    cancellationTokenSource.Cancel();
    autoResetEvent.WaitOne();

    foreach (MailMessage mailMessage in mailMessages)
        mailMessage.Dispose();

    if (exception is OperationCanceledException)
        Console.WriteLine("Operation has been interrupted: " + exception.Message);
}