Is there a non-unique-key sorted list generic collection in C#?
I'm a bit surprised by System.Collections.Generic.SortedList, in that
- It requires me to use
<key, value>instead of<value>(comparer) - It only allows on entry per value
These seem quirky in the way I want to use it (although I'm sure they're just right for other situations). Is there another collection that doesn't have these two characteristics?
Answer
SortedList<,> is really a map sorted by key, not a list. Bad naming, maybe. But there are ways to emulate what you want, depending on your exact requirements. You could, for example, encapsulate a SortedList<T, int> and have add/remove something like:
// add
int count;
if(list.TryGetValue(value, out count)) list[value] = count+1;
else list[value] = 1;
Ultimately you could use a simple list (List<>) too - it depends what you are doing.
In part, I expect that data-binding etc makes it hard to implement a regular list that sorts immediately - you need to implement a lot of interfaces to get that working, as normally it expects the item you add to stay at the end.