C# Syntax - Split String into Array by Comma, Convert To Generic List, and Reverse Order

What is the correct syntax for this:

IList<string> names = "Tom,Scott,Bob".Split(',').ToList<string>().Reverse();

What am I messing up? What does TSource mean?

From stackoverflow

• Try this:

  List<string> names = new List<string>("Tom,Scott,Bob".Split(','));
  names.Reverse();
  

  tyndall : I get the error - Cannot implicitly convert type 'void' to 'System.Collections.Generic.List

  Y Low : I just tried it and it worked perfectly

• The problem is that you're calling List<T>.Reverse() which returns void.

  You could either do:

  List<string> names = "Tom,Scott,Bob".Split(',').ToList<string>();
  names.Reverse();
  

  or:

  IList<string> names = "Tom,Scott,Bob".Split(',').Reverse().ToList<string>();
  

  The latter is more expensive, as reversing an arbitrary IEnumerable<T> involves buffering all of the data and then yielding it all - whereas List<T> can do all the reversing "in-place". (The difference here is that it's calling the Enumerable.Reverse<T>() extension method, instead of the List<T>.Reverse() instance method.)

  More efficient yet, you could use:

  string[] namesArray = "Tom,Scott,Bob".Split(',');
  List<string> namesList = new List<string>(namesArray.Length);
  namesList.AddRange(namesArray);
  namesList.Reverse();
  

  This avoids creating any buffers of an inappropriate size - at the cost of taking four statements where one will do... As ever, weigh up readability against performance in the real use case.

  flesh : skeet's a beast!

• List<string> names = "Tom,Scott,Bob".Split(',').Reverse().ToList();
  

  This one works.

• What your missing here is that .Reverse() is a void method. It's not possible to assign the result of .Reverse() to a variable. You can however alter the order to use Enumerable.Reverse() and get your result

  var x = "Tom,Scott,Bob".Split(',').Reverse().ToList<string>()
  

  The difference is that Enumerable.Reverse() returns an IEnumerable<T> instead of being void return

• Or we can use LINQ to get the same result

  var result = from s in "Tom,Scott,Bob".Split(',') orderby s descending select s;