Question

I am using LINQ like

from a in b.Descendants("SomeNode")
select new MyClass
    {
      isfirst= false, 
      islast = false,
    };

How can I get the position of the element here? I basically want to know which one is first and which one is last element.

Answer 1

Something like …

var res = b.Select((l, i) => 
          new MyClass { IsFirst = (i == 0), IsLast = (i == b.Count-1) });

… should work.

Per comment: Changed anonymous class to concrete class. This assumes that IsFirst and IsLast are boolean properties with a setter on a class called MyClass.