/// <summary>
/// Send a message via SMTP, optionally, bypass the RCPT TO recipients with the added rcpto collection.
/// Otherwise, default behavior is to send to all recipients listed in To, Cc, and Bcc.
/// </summary>
/// <param name="message"></param>
/// <param name="rcptToRecipients"></param>
public void Send(MailMessage message, IEnumerable <MailAddress> rcptToRecipients = null)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Enter(this, message);
}
if (_disposed)
{
throw new ObjectDisposedException(GetType().FullName);
}
try
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Info(this, $"DeliveryMethod={DeliveryMethod}");
NetEventSource.Associate(this, message);
}
SmtpFailedRecipientException recipientException = null;
if (InCall)
{
throw new InvalidOperationException(Strings.net_inasync);
}
if (message == null)
{
throw new ArgumentNullException(nameof(message));
}
if (DeliveryMethod == SmtpDeliveryMethod.Network)
{
CheckHostAndPort();
}
MailAddressCollection recipients = new MailAddressCollection();
if (message.From == null)
{
throw new InvalidOperationException(Strings.SmtpFromRequired);
}
var rcptTo = (rcptToRecipients ?? Enumerable.Empty <MailAddress>()).ToArray();
if (rcptTo.Length > 0)
{
foreach (var i in rcptTo)
{
recipients.Add(i);
}
}
else
{
if (message.To != null)
{
foreach (MailAddress address in message.To)
{
recipients.Add(address);
}
}
if (message.Bcc != null)
{
foreach (MailAddress address in message.Bcc)
{
recipients.Add(address);
}
}
if (message.CC != null)
{
foreach (MailAddress address in message.CC)
{
recipients.Add(address);
}
}
}
if (recipients.Count == 0)
{
throw new InvalidOperationException(Strings.SmtpRecipientRequired);
}
_transport.IdentityRequired = false; // everything completes on the same thread.
try
{
InCall = true;
_timedOut = false;
_timer = new Timer(new TimerCallback(TimeOutCallback), null, Timeout, Timeout);
bool allowUnicode = false;
string pickupDirectory = PickupDirectoryLocation;
MailWriter writer;
switch (DeliveryMethod)
{
case SmtpDeliveryMethod.PickupDirectoryFromIis:
throw new NotSupportedException(Strings.SmtpGetIisPickupDirectoryNotSupported);
case SmtpDeliveryMethod.SpecifiedPickupDirectory:
if (EnableSsl)
{
throw new SmtpException(Strings.SmtpPickupDirectoryDoesnotSupportSsl);
}
allowUnicode = IsUnicodeSupported(); // Determend by the DeliveryFormat paramiter
ValidateUnicodeRequirement(message, recipients, allowUnicode);
writer = GetFileMailWriter(pickupDirectory);
break;
case SmtpDeliveryMethod.Network:
default:
GetConnection();
// Detected durring GetConnection(), restrictable using the DeliveryFormat paramiter
allowUnicode = IsUnicodeSupported();
ValidateUnicodeRequirement(message, recipients, allowUnicode);
writer = _transport.SendMail(message.Sender ?? message.From, recipients,
message.BuildDeliveryStatusNotificationString(), allowUnicode, out recipientException);
break;
}
_message = message;
message.Send(writer, DeliveryMethod != SmtpDeliveryMethod.Network, allowUnicode);
writer.Close();
_transport.ReleaseConnection();
//throw if we couldn't send to any of the recipients
if (DeliveryMethod == SmtpDeliveryMethod.Network && recipientException != null)
{
throw recipientException;
}
}
catch (Exception e)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Error(this, e);
}
if (e is SmtpFailedRecipientException && !((SmtpFailedRecipientException)e).fatal)
{
throw;
}
Abort();
if (_timedOut)
{
throw new SmtpException(Strings.net_timeout);
}
if (e is SecurityException ||
e is AuthenticationException ||
e is SmtpException)
{
throw;
}
throw new SmtpException(Strings.SmtpSendMailFailure, e);
}
finally
{
InCall = false;
if (_timer != null)
{
_timer.Dispose();
}
}
}
finally
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Exit(this);
}
}
}
