protected virtual void OnCollectionChanged(DictionaryChangedEventArgs <TKey, TValue> changeAction)
{
var tasks = new List <Task> {
Task.Run(() => CollectionChanged?.Invoke(this, changeAction))
};
if (changeAction.Action != NotifyCollectionChangedAction.Reset &&
_observers.TryGetValue(changeAction.Key, out var observers))
{
tasks.AddRange(observers.Select(o => Task.Run(() => o.OnEventOccur(changeAction))));
}
Task.WaitAll(tasks.ToArray());
}
public void OnEventOccur(DictionaryChangedEventArgs <TKey, TValue> args)
{
_action.Invoke(args);
}