C#预处理指令

下面的程序演示了条件指令的用法：

#define DEBUG #define VC_V10 using System; public class TestClass { public static void Main() { #if (DEBUG && !VC_V10) Console.WriteLine("DEBUG is defined"); #elif (!DEBUG && VC_V10) Console.WriteLine("VC_V10 is defined"); #elif (DEBUG && VC_V10) Console.WriteLine("DEBUG and VC_V10 are defined"); #else Console.WriteLine("DEBUG and VC_V10 are not defined"); #endif Console.ReadKey(); } }

当上面的代码被编译和执行时，它会产生下列结果：

DEBUG and VC_V10 are defined