using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        List<int> list = null;

​

        if (list.IsNullOrEmpty())

        {

            Console.WriteLine("List is null or empty");

        }

    }

}

​

public static class ListExtensions

{

    public static bool IsNullOrEmpty<T>(this IEnumerable<T> list)

    {

        // First check if list is null, then check if it's empty

        return list == null || list.Count() == 0 ;

    }

}