Sends an empty message within a conversation.
procedure SendEmpty(const MessageType: string = '');
Sends an empty message within a conversation. The target service is determined when creating a conversation.
This method must be used to send an empty message. This is the only method that can be used to send a message if MessageType was created with the Validation property set to mvEmpty.
The MessageType parameter determines the type of the message being sent. For the detailed description of the message types see the description of the CREATE MESSAGE TYPE statement in MSDN.