Problem with loosely coupled events

[Mark Ritchie]

I've been fighting with loosely coupled events for the last couple of days,
and currently have the following scenario:



Interface


namespace MyAssembly

{

public interface IMySink

{

void OnSyncEvent();

}



[EventClass]

public class MyEventClass : ServicedComponent,IMySink

{

public void OnSyncEvent ()

{

throw(new NotImplementedException(exception));

}

const string exception = @"You should not call an event class
directly. Register this assembly using RegSvcs /reconfig";

}

}





Message Class


public class MyMessage

{

public string Forename;

public string Surname;

}



Publisher


IMySink sink = new MyEventClass();

MyMessage myMessageObj = new MyMessage();

myMessageObj.Forename = "John";

myMessageObj.Surname = "Smith";



// Code for SerializeThis not included

string myMessageStr = SerializeThis(myMessageObj);

sink.OnSyncEvent(myMessageStr);





Subscriber


class SynchronisationSubscriberClass :ServicedComponent, IMySink

{

private MyWindowsFormClass formWindow;



public MyWindowsFormClass FormWindow

{

set {formWindow = value;}

}



public void OnSyncEvent (string message)

{

MyMessage myMessageObj = DeserializeThis(message);

formWindow.DoSomethingWithMessage(myMessageObj);

}

}





Problem


When the OnSyncEvent method is called in the subscriber the instance of
formWindow is null. I presume this is because the code is running in a COM+'
s memory space and not the memory space that the rest of the application
which instantiated the subscriber is running. If this is the case how do I
hook back into my main application? Hopefully somebody out there can help me
as Microsoft's help in this area is next to non-existent.

 

[Willy Denoyette [MVP]]

Not sure what you expect, FormWindow is a property of the
SynchronisationSubscriberClass class, but nowhere you set this property,
the only thing you do is fire an event at least in the snip of code you
posted.

Willy.