Question

Let’s say I have a property:

public Collection<T> GameCollection
{
  get { return new Collection<T>(_myGameList); }
}

Would this method creates new Collection object every time it’s called?

Answer 1

Yes, it would, because of the new. However it does not duplicate myGameList or its contents; it only makes new wrappers for the same myGameList (see Collection(IList<T>) constructor).

If you want to prevent any of that and return a single collection, you can initialize a backing field instead and have your getter get that field (assuming _myGameList is already initialized too):

private Collection<T> _myGameCollection = new Collection<T>(_myGameList);

public Collection<T> GameCollection
{
  get { return _myGameCollection; }
}