.Net smtp SendMailAsync function 返回 IsCanceled

Question

我對SendMailAsync例程有疑問。 在ContinueWith()方法中，我使用的是SendMailContinuation()方法，其中task.IsCanceled始終為真。

.Net 版本 4.6.1

private void SendEMail()
{
    try
    {
        using (SmtpClient smtpClient = new SmtpClient(EmailServerAddress))
        {
            _logger.Info("Sending Email to: {0} ", recipient);
            MailAddress from = new MailAddress(EmailAddress, EmailAddress, Encoding.UTF8),
                        to = new MailAddress(recipient, recipient, Encoding.UTF8);
            
            using (MailMessage message = new MailMessage(from, to))
            {
                message.SubjectEncoding = Encoding.UTF8;
                message.Priority = MailPriority.High;
                message.Body = "";
                message.BodyEncoding = Encoding.UTF8;
            
                smtpClient.Credentials = new NetworkCredential(UserName, UserPassword);
            
                smtpClient.SendMailAsync(message)
                        .ContinueWith(SendMailContinuation);
        }
    }
    catch (Exception ex)
    {
        _logger.Error(ex);
    }
}
private void SendMailContinuation(Task task)
{
    if (task.IsFaulted)
    {
        _logger.Error(task.Exception);
    }
    else if (task.IsCanceled)
    {
        _logger.Warn(task.Status);
    }
}

Answer 1

您應該等待 smtpClient.SendMailAsync() function。 您可以通過將 function 'SendEMail()' 設為異步任務並在 smtpClient.SendMailAsync() 調用之前添加 await 來做到這一點。