/// <summary>
/// Removes child from list of events.
/// </summary>
/// <param name="item">Child to remove.</param>
public void InvalidateChildReference(SubscriptionEventInfo item)
{
Events.Remove(item);
item = null;
if (Events.Count == 0)
{
InvalidateReference();
}
}
/// <summary>
/// Initializes a new instance of the <see cref="SubscriberInfo"/> class.
/// </summary>
/// <param name="parent">Parent container.</param>
/// <param name="subscriber">Object receiving notifications.</param>
/// <param name="subscriberType">Type of object receiving notifications.</param>
/// <param name="eventHandler">Method that will be invoked to handle notification.</param>
public SubscriberInfo(SubscriptionEventInfo parent, object subscriber, Type subscriberType, EventHandler eventHandler)
{
if (object.ReferenceEquals(null, subscriber))
{
throw new ArgumentNullException(nameof(subscriber));
}
_subscriberReference = new WeakReference(subscriber);
SubscriberType = subscriberType;
EventHandlerMethodName = null;
_parent = parent;
Handler = eventHandler;
}
/// <summary>
/// Creates a new subscription. If a subscription with the same parameters already exists, nothing happens.
/// </summary>
/// <typeparam name="TSubscribeTo">Type of object being subscribed to, that will transmit event.</typeparam>
/// <typeparam name="TSubscriber">Type of object receiving notifications.</typeparam>
/// <param name="subscribeToEvent">Name of the event to subscribe to.</param>
/// <param name="subscriber">Object receiving notifications.</param>
/// <param name="eventHandler">Method that will be invoked to handle notification.</param>
public static void Subscribe <TSubscribeTo, TSubscriber>(string subscribeToEvent, TSubscriber subscriber, EventHandler eventHandler)
{
SubscriptionContainerInfo newSubscriptionContainer = null;
SubscriptionEventInfo newEventInfo = null;
SubscriberInfo newSubscriber = null;
var subscribeToContainerType = typeof(TSubscribeTo);
var subscriberType = typeof(TSubscriber);
var currentSubscriptions = _subscriptions.Where(x => x.SubscribeToContainerType == subscribeToContainerType);
foreach (var subscriptionContainer in currentSubscriptions)
{
var eventInfos = subscriptionContainer.Events.Where(x => x.EventName == subscribeToEvent);
foreach (var eventInfo in eventInfos)
{
var existingSubscriber = eventInfo
.Subscribers
.Where(x => x.SubscriberType == subscriberType && x.Handler == eventHandler)
.FirstOrDefault();
if (!object.ReferenceEquals(null, existingSubscriber))
{
return;
}
newSubscriber = new SubscriberInfo(eventInfo, subscriber, subscriberType, eventHandler);
eventInfo.Subscribers.Add(newSubscriber);
return;
}
// else, not found in Events.
newEventInfo = new SubscriptionEventInfo(subscriptionContainer, subscribeToEvent);
newSubscriber = new SubscriberInfo(newEventInfo, subscriber, subscriberType, eventHandler);
newEventInfo.Subscribers.Add(newSubscriber);
subscriptionContainer.Events.Add(newEventInfo);
return;
}
// else, not found in current subscriptions
newSubscriptionContainer = new SubscriptionContainerInfo(subscribeToContainerType);
newEventInfo = new SubscriptionEventInfo(newSubscriptionContainer, subscribeToEvent);
newSubscriber = new SubscriberInfo(newEventInfo, subscriber, subscriberType, eventHandler);
newEventInfo.Subscribers.Add(newSubscriber);
newSubscriptionContainer.Events.Add(newEventInfo);
_subscriptions.Add(newSubscriptionContainer);
}
/// <summary>
/// Initializes a new instance of the <see cref="SubscriberInfo"/> class.
/// </summary>
/// <param name="parent">Parent container.</param>
/// <param name="subscriber">Object receiving notifications.</param>
/// <param name="subscriberType">Type of object receiving notifications.</param>
/// <param name="eventHandlerMethodName">Name of method that will be invoked via reflection to handle notification.</param>
public SubscriberInfo(SubscriptionEventInfo parent, object subscriber, Type subscriberType, string eventHandlerMethodName)
{
if (object.ReferenceEquals(null, subscriber))
{
throw new ArgumentNullException(nameof(subscriber));
}
_subscriberReference = new WeakReference(subscriber);
SubscriberType = subscriberType;
EventHandlerMethodName = eventHandlerMethodName;
Handler = null;
_parent = parent;
_methodInfo = SubscriberType.GetMethod(EventHandlerMethodName);
if (object.ReferenceEquals(null, _methodInfo))
{
throw new ArgumentException($"Could not find {eventHandlerMethodName} on type {subscriberType.FullName}");
}
}
