.net - How to make IEnumerable<string>.Contains case-insensitive?

Question

Suppose I have a .net Array of strings.

string[] strings = new string[] { "AbC", "123", "Xyz", "321" };

If I wanted to see if the array of strings contains "ABC", I could write

strings.Contains("ABC");

However, suppose that I want a function that will return true if the uppercase values of the strings contain "ABC". I could uppercase the entire array, but it looks like the .Contains method has some overloads for specifying the comparison, but I'm confused by the syntax.

How can I use the IEnumerable<string>.Contains() method implement this logic?

Answer 1

Use overloaded Enumerable.Contains method which accepts equality comparer:

strings.Contains("ABC", StringComparer.InvariantCultureIgnoreCase)

Also there is strings comparer in box which you can use.