using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        var list = new LinkedList<int>(new [] { 1, 2, 3, 4, 5, 6});

        foreach (var node in list.ToNodes())

        {

            Console.WriteLine($"Is next node null - {node.Next == null}");

            if (node.Value % 2 == 0) list.Remove(node);

        }

    }

}

​

public static class LinkedListExtensions

{

    public static IEnumerable<LinkedListNode<T>> ToNodes<T>(this LinkedList<T> linkedList)

    {

        var current = linkedList.First;

        while (current != null)

        {

            // Memorizing next node in case we Removed current from the list while iterating

            var next = current.Next;

            yield return current;

            current = next;

        }

    }

}