The OnLogout event occurs after the client has
successfully logged out using the QUIT command or reinitialized the
session using the REIN command.
The application should not depend on this event handler always
being invoked when a client is disconnected from the server. This
event only occurs when the client sends the QUIT or REIN commands and
will not be invoked if the client connection is aborted or
disconnected for some other reason, such as exceeding the idle timeout
period. If the application needs to update data structures or perform
some cleanup when a client disconnects, that should be done in the
OnDisconnect event handler.
The application should not call the Disconnect
method in the handler for this event because the client is either in
the process of disconnecting or expects that it can submit new
credentials to the server.