Data Type C# Tutorial

public static class PartialComparer
    {
        public static int? ReferenceCompare(T first, T second) where T : class{
            if (first == second){
                return 0;
            }
            if (first == null){
                return -1;
            }
            if (second == null){
                return 1;
            }
            return null;
        }
    }