How do I tell if an action is a lambda expression?
- by Keith
I am using the EventAgregator pattern to subscribe and publish events. If a user subscribes to the event using a lambda expression, they must use a strong reference, not a weak reference, otherwise the expression can be garbage collected before the publish will execute.
I wanted to add a simple check in the DelegateReference so that if a programmer passes in a lambda expression and is using a weak reference, that I throw an argument exception. This is to help "police" the code.
Example:
eventAggregator.GetEvent<RuleScheduler.JobExecutedEvent>().Subscribe
(
e => resetEvent.Set(),
ThreadOption.PublisherThread,
false,
// filter event, only interested in the job that this object started
e => e.Value1.JobDetail.Name == jobName
);
public DelegateReference(Delegate @delegate, bool keepReferenceAlive)
{
if (@delegate == null)
throw new ArgumentNullException("delegate");
if (keepReferenceAlive)
{
this._delegate = @delegate;
}
else
{
//TODO: throw exception if target is a lambda expression
_weakReference = new WeakReference(@delegate.Target);
_method = @delegate.Method;
_delegateType = @delegate.GetType();
}
}
any ideas?
I thought I could check for @delegate.Method.IsStatic but I don't believe that works... (is every lambda expression a static?)
