High performance “contains” search in list of strings in C#

Question

I have a list of approx. 500,000 strings, each approx. 100 characters long. Given a search term, I want to identify all strings in the list that contain the search term. At

Answer 1

You should try to use Dictionary class. It's much faster than List because it's an indexed search.

Dictionary ldapDocument = new Dictionary();
//load your list here
//Sample -> ldapDocument.Add("014548787","014548787");
var match = ldapDocument.ContainsKey(stringToMatch);