Add new value before the specified existing node in LinkedList in CSharp

using System;//from   ww  w . jav  a2  s .c  om
using System.Collections;
using System.Collections.Generic;

public class GenericCollection  
{
   public static void Main()  
   {
      LinkedList<String> ll = new LinkedList<String>();
      ll.AddLast( "A" );
      ll.AddLast( "B" );
      ll.AddLast( "C" );
      ll.AddLast( "java2s.com" );

      foreach(string s in ll){
          Console.WriteLine(s);
      }
      ll.AddBefore(ll.First,"Z" );

      foreach(string s in ll){
          Console.WriteLine(s);
      }
   }
}