C# List.ForEach(delegate(type t) and how to remove items as the list is iterated through

Question

This may be considered bad programming, but prior to .net 4, I used to heavily use code similar to this: ``` enemyList.ForEach(delegate(Enemy e) { e.Update(); if (someCondition) enemyList.Remove(e); }); ``` Now, I'm going through an updating some old projects, and there are a LOT of code thats going to have to be changed since ForEach was removed.. Now, I do have an extension to allow me to use the ForEach : ``` public static void ForEach(this IEnumerable sequence, Action action) { if (sequence == null) throw new ArgumentNullException("sequence"); if (action == null) throw new ArgumentNullException("action"); foreach (T item in sequence) action(item); } ``` I know I can do this: ``` var index = 0; while(index < enemyList.Count) { if(condition) enemyList.RemoveAt(index); else index++; } ``` But some of those would be a pain to rewrite like that.. Is there any way to add that functionality back so that I can iterate through that list, remove the items I need without having to g…

Accepted Answer

Use the list's `RemoveAll` method.

You can refactor the code to:

```
enemyList.RemoveAll(enemy => enemy.SomeCondition);
```

Not only is it better than the `while` loop, I'd argue it's quite a bit better than the `Foreach` method.

C# List<t>.ForEach(delegate(type t) and how to remove items as the list is iterated through

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