Question

I have a string List<string> this would apply to all Lists. I needed to get the first item in a string list and then convert what I got back to a string.

Here is the working code using linq:

public List<string> AppGroup = new List<string>();
var group = SearchParameters.AppGroup.Take(1);
string firstAppGroup = String.Join(",", group.ToArray());

My question would be; Is this the best method to do what I am going for? Is there a better or shorter way to write this out? A good example of considering performance would be appreciated. If what I have is fine and no changes are needed, please let me know.

I am using framework 3.5 and above.

Answer 1

Your current means of grabbing the first item in the list is somewhat long-winded, and stems from the fact that using Take(1) returns an IEnumerable rather than the item in question.

Assuming SearchParameters.AppGroup is List<string>

string firstAppGroup = 
  SearchParameters.AppGroup.FirstOrDefault(); //returns null on empty set

is a much briefer way of stating the same intent.

EDIT:

As @CodeInChaos states, if you don’t want to deal with a null value, use the null-coalescing operator to substitute an empty string in the case that null is returned:

string firstAppGroup = 
  SearchParameters.AppGroup.FirstOrDefault() ?? string.Empty;