Re: how to wrap your brain around delegates?

"Peter Morris [Droopy eyes software]" <pete@xxxxxxxxxxxxxxxxxxxxxx> a écrit
dans le message de news: 448dae05@xxxxxxxxxxxxxxxxxxxxxxxxx

| I thought that events were multi-cast, not delegates. A delegate is just
a
| method signature declaration.

Well, this is where I am a bit flummoxed. You have to declare an event if
you are declaring a property, but you can simply declare a field of the
delegate type to support that property.

e.g.

public class NotificationEventArgs : EventArgs
{
private object aspect;

public NotificationEventArgs(object aspect)
{
this.aspect = aspect;
}

public object Aspect
{
get { return aspect; }
}
}

public delegate void NotificationHandler(object sender,
NotificationEventArgs args);

public class SubjectImplementer
{
private NotificationHandler notify;

public void OnNotify(object sender, object aspect)
{
if (notify != null)
{
NotificationEventArgs args = new NotificationEventArgs(aspect);
notify(sender, args);
}
}

public event NotificationHandler Notify
{
add { notify += value; }
remove { notify -= value; }
}
}

So the field is treated as multicast by the property !! ??

Joanna

--
Joanna Carter [TeamB]
Consultant Software Engineer


.

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