private const int Total = 500000;
    private static volatile int _count = 0;

    private static void Main()
    {
        Task task = Task.Factory.StartNew(Decrement);
        for (int i = 0; i < Total; i++)
        {
            _count++;
        }

        task.Wait();
        Console.WriteLine(_count);

        Console.ReadLine();
    }

    private static void Decrement()
    {
        for (int i = 0; i < Total; i++)
        {
            _count--;
        }
    }

有时结果为0,有时结果为-xxxxxx.我不知道为什么.任何人都可以解释它并告诉我正确的用法.