小编Asa*_*rds的帖子

在C＃中，如果预处理程序指令是在实际编译之前进行预处理的指令，那么为什么不在该程序中首先执行该指令？

static void Main(string[] args)
        {
            Program1.display();
            Program2 p2 = new Program2();
            p2.show();
#if DEBUG
Console.WriteLine("DEBUG from preprocessor directive is working!");
#endif
        }

预期产量：

DEBUG from preprocessor directive is working!
.......(from display())
.......(from show())

但是实际输出：

.......(from display())
.......(from show())
DEBUG from preprocessor directive is working!