The reference to a registered handler.
public interface IRegistration
Such a handler reference is provided whenever a handler with a server side presence is registered.
Added in version 5.1.
Requests that the handler is unregistered from the server.
After the handler is unregistered, the handler's
method will be called.
A handler can only be unregistered once. A given instance will return the
Task if this method is called more than once.
If the returned
Task completes successfully, the result
Added in version 6.1.
The session is closed. Thrown by the returned