How to ignore the case sensitivity in List<string>

Question

Let us say I have this code

string seachKeyword = ""; List<string> sl = new List<string>(); sl.Add("store"); sl.Add("State"); sl.Add("STAMP"); sl.Add("Crawl"); sl.Add("Crow"); List<string> searchResults = sl.FindAll(s => s.Contains(seachKeyword)); 

How can I ignore the letter case in Contains search?

Thanks,

Answer 1

Use Linq, this adds a new method to .Compare

using System.Linq; using System.Collections.Generic;  List<string> MyList = new List<string>(); MyList.Add(...) if (MyList.Contains(TestString, StringComparer.CurrentCultureIgnoreCase)) {     //found }  

so presumably

using System.Linq; ...  List<string> searchResults = sl.FindAll(s => s.Contains(seachKeyword, StringComparer.CurrentCultureIgnoreCase));   

Answer 2

The best option would be using the ordinal case-insensitive comparison, however the Contains method does not support it.

You can use the following to do this:

sl.FindAll(s => s.IndexOf(searchKeyword, StringComparison.OrdinalIgnoreCase) >= 0); 

It would be better to wrap this in an extension method, such as:

public static bool Contains(this string target, string value, StringComparison comparison) {     return target.IndexOf(value, comparison) >= 0; } 

So you could use:

sl.FindAll(s => s.Contains(searchKeyword, StringComparison.OrdinalIgnoreCase));