/// <summary>
/// This method is called when asynchronous Connect method completes.
/// </summary>
/// <param name="ar">An IAsyncResult that stores state information and any user defined data for this asynchronous operation.</param>
private void ConnectCallback(IAsyncResult ar)
{
try{
m_pSmtpClient.EndConnect(ar);
// Start TLS requested, start switching to SSL.
if (m_pActiveTarget.SslMode == SslMode.TLS)
{
m_pSmtpClient.BeginStartTLS(new AsyncCallback(this.StartTlsCallback), null);
}
// Authentication requested, start authenticating.
else if (!string.IsNullOrEmpty(m_pActiveTarget.UserName))
{
m_pSmtpClient.BeginAuthenticate(m_pActiveTarget.UserName, m_pActiveTarget.Password, new AsyncCallback(this.AuthenticateCallback), null);
}
else
{
long messageSize = -1;
try{
messageSize = m_pRelayItem.MessageStream.Length - m_pRelayItem.MessageStream.Position;
}
catch {
// Stream doesn't support seeking.
}
m_pSmtpClient.BeginMailFrom(
this.From,
messageSize,
IsDsnSupported() ? m_pRelayItem.DSN_Ret : SMTP_DSN_Ret.NotSpecified,
IsDsnSupported() ? m_pRelayItem.EnvelopeID : null,
new AsyncCallback(this.MailFromCallback),
null
);
}
}
catch (Exception x) {
try{
// Release IP usage.
m_pServer.RemoveIpUsage(m_pActiveTarget.Target.Address);
m_pActiveTarget = null;
// Connect failed, if there are more target IPs, try next one.
if (!this.IsDisposed && !this.IsConnected && m_pTargets.Count > 0)
{
BeginConnect();
}
else
{
Dispose(x);
}
}
catch (Exception xx) {
Dispose(xx);
}
}
}
