Linq: How to get second last

Question

So i have a List of strings that looks like this:

var ls=new List<string>()
    {
        "100",
        "101-102-1002",
        "105-153-1532-1532",
        "105-1854-45-198",
        "180-95-45-200"
    };

I want to get the second last of the the split string. So my output looks like this:

null,
102,
1532,
45,
45

I have a solution for it that looks like this:

ls.Select (l =>l.Split('-').Select ((s,i) =>new {s,i})
.OrderByDescending (x=>x.i).Skip(1).Take(1))

I think that this solution might be to complex for this simple task. So my question is: Do any of you have a simpler solution to this problem?

Answer 1

Reverse fits well here:

ls.SelectMany(l =>l.Split('-').Reverse().Skip(1).Take(1).DefaultIfEmpty())

I also use SelectMany to transform IEnumerable<IEnumerable<string>> to <IEnumerable<string>.

Answer 2

        var ls = new List<string>() { "100", "101-102-1002", "105-153-1532-1532", "12-1235-785" };
        var result = from p in ls
                     let arr = p.Split('-')
                     select arr.Length < 2 ? null : arr[arr.Length - 2];

        foreach (var item in result)
        {
            Console.WriteLine(item);
        }



        Console.Read();

Answer 3

If you have

var ls = new List<string>( ... );

then

var result = ls.Reverse().Skip(1).Take(1);

should work.