using System;

using System.Threading.Tasks;

public class Program

{

    public static void Main()

    {

        var x = 0;

​

        var myList = new[] { "hello" };

​

        Parallel.ForEach(myList, item =>

        {

            x = 3;

        });

​

        if (x != 0)

        {

            Console.WriteLine("x is not zero");

        }

    }

}