Get a List<string> of variables within a List<T>

Question

I currently have a List<T> made up of the following class:

int id { get; set; }
string title { get; set; }
string description { get; set; }

I want to create a List<string> of only all the title's in the List

Which would be the best performance way to do this?

Edit My Description field averages 2k characters... I dont want that to slow down only getting titles.

Edit2 I am using MVC's Code first (Entity Framework). The List<T> is stored in the _context, which I query from to get the data.

Edit3 IF possible .. Is there a way to get the Title AND ID ?

Answer 1

I want to create a List<string> of only all the title's in the List

You can use projection via Select.

var list = new List<SomeClass>();

var titleList = list.Select(x => x.title).ToList();

See Getting Started with LINQ in C# for more information on LINQ extension methods.

IF possible .. Is there a way to get the Title AND ID ?

You can use an Anonymous Type to put all three properties in one list:

var entityList = list.Select(x => new { x.title, x.id, x.description }).ToList();

Which would be the best performance way to do this?

var list = new List<SomeClass>();
var titleList = new List<string>(list.Count);

foreach(var item in list)
{
    titleList.Add(item.title);
}

LINQ will not outperform a simple foreach statement, but that's a tradeoff you should evaluate by benchmarking since the difference is negligible in most cases.

Microbenchmark