Question

I’m looking through a generic list to find items based on a certain parameter.

In General, what would be the best and fastest implementation?
1. Looping through each item in the list and saving each match to a new list and returning that

foreach(string s in list) {      if(s == 'match')     {        newList.Add(s);     } }   return newList; 

Or
2. Using the FindAll method and passing it a delegate.

newList = list.FindAll(delegate(string s){return s == 'match';}); 

Don’t they both run in ~ O(N)? What would be the best practice here?

Regards, Jonathan

Answer 1

You should definitely use the FindAll method, or the equivalent LINQ method. Also, consider using the more concise lambda instead of your delegate if you can (requires C# 3.0):

var list = new List<string>(); var newList = list.FindAll(s => s.Equals('match'));