Best Practice - Removing item from generic collection in C#
- by Matt Davis
I'm using C# in Visual Studio 2008 with .NET 3.5.
I have a generic dictionary that maps types of events to a generic list of subscribers. A subscriber can be subscribed to more than one event.
private static Dictionary<EventType, List<ISubscriber>> _subscriptions;
To remove a subscriber from the subscription list, I can use either of these two options.
Option 1:
ISubscriber subscriber; // defined elsewhere
foreach (EventType event in _subscriptions.Keys) {
if (_subscriptions[event].Contains(subscriber)) {
_subscriptions[event].Remove(subscriber);
}
}
Option 2:
ISubscriber subscriber; // defined elsewhere
foreach (EventType event in _subscriptions.Keys) {
_subscriptions[event].Remove(subscriber);
}
I have two questions.
First, notice that Option 1 checks for existence before removing the item, while Option 2 uses a brute force removal since Remove() does not throw an exception. Of these two, which is the preferred, "best-practice" way to do this?
Second, is there another, "cleaner," more elegant way to do this, perhaps with a lambda expression or using a LINQ extension? I'm still getting acclimated to these two features.
Thanks.
EDIT
Just to clarify, I realize that the choice between Options 1 and 2 is a choice of speed (Option 2) versus maintainability (Option 1). In this particular case, I'm not necessarily trying to optimize the code, although that is certainly a worthy consideration. What I'm trying to understand is if there is a generally well-established practice for doing this. If not, which option would you use in your own code?
