Wanted: .Net collection that stores a bunch of case insensitive strings fast and efficient

I'm looking for a simple collection that will store a bunch of strings in a case insensitive way开发者_运维百科. I need at least a Contains() and Remove() method to see if a certain string is present and to remove that string.

I've tried List<string> but that one is case sensitive. I need could use a case insensitive Dictionary<TKey, T>, but that "feels" like a waste of space. Doing a ToLower() on each string is a waste of performance.

Does anyone know what kind .Net collection I should use?

You should use a new HashSet<string>(StringComparer.OrdinalIgnoreCase).
Note that this is an unordered set.

You could use a StringDictionary.

Had the same problem to solve today. If you can include Linq, then your List gets overloaded methods with a comparer.

using System.Linq;

List<string> stringList = new List<string>();
stringList.Contains("hello", StringComparer.OrdinalIgnoreCase);

Hope this helps: Martin

By default Dictionary are not case in-sensitive. But you can implement your own variant to make it in-sensitive. (I might be wrong on this :D)

I had same issue with Dictionary but then after trying a lot of IEquality implementations, finally I settled the score with LINQ.

string k = customers.Where(c => c.Key.Equals(valueToSearch, StringComparison.OrdinalIgnoreCase)).FirstOrDefault().Key;

if (!string.IsNullOrEmpty(k) && k.ToUpper() == valueToSearch.ToUpper())
{
    // Do some thing
}

Hope this will help somebody in future.

Sanjay Zalke

Write your own Contains() and Remove() methods, which perform the case insensitve comparison.