LINQ ToList Query Operator

The ToList<TSource>(IEnumerable<TSource>) method forces immediate query evaluation and returns a List<T> that contains the query results. You can append this method to your query in order to obtain a cached copy of the query results.

string[] fruits = { "apple", "passionfruit", "banana", "mango",
                                    "orange", "blueberry", "grape", "strawberry" };

           List<int> lengths = fruits.Select(fruit => fruit.Length).ToList();

             foreach (int length in lengths)
            {
               Console.WriteLine(length);
            }

            /*
             This code produces the following output:

             5
             12
             6
             5
             6
             9
             5
             10
            */