Find case insensitive index in IList

Question

I've found answers to determining if an IList<string> contains an element using case insensitive contains: ilist.Contains(element, StringComparer.CurrentCultureIgnoreCase)

But what I would like to do is find the element itself that corresponds within the IList to the element I'm searching for. For instance if the IList contains {Foo, Bar} and I search for fOo I'd like to be able to receive Foo.

I'm not worried about multiples, and the IList doesn't seem to contain any function other than IndexOf with doesn't help me much.

EDIT: As I'm using IList and not List, I don't have the function IndexOf, so the answer posted on here doesn't help me much :)

Answer 1

To find the index of the item you could use the FindIndex function with a custom predicate doing the case-insensitve match. Similarly, you can use Find to get the actual item.

I'd probably create an extension method to use as an overload.

public static int IndexOf(this List<string> list, string value, StringComparer comparer)
{
    return list.FindIndex(i => comparer.Equals(i, value));
}

public static int CaseInsensitiveIndexOf(this List<string> list, string value)
{
    return IndexOf(list, value, StringComparer.CurrentCultureIgnoreCase);
}

public static string CaseInsensitiveFind(this List<string> list, string value)
{
    return list.Find(i => StringComparer.CurrentCultureIgnoreCase.Equals(i, value));
}