Since the purpose of these COMPILER directives are to tell the compiler NOT to include code, debug code,beta code, or perhaps code that is needed by all of your end users, except say those the advertising department, i.e. #Define AdDept you want to be able include or remove them based on your needs. Without having to change your source code if for example a non AdDept merges into the AdDept. Then all that needs to be done is to include the #AdDept directive in the compiler options properties page of an existing version of the program and do a compile and wa la! the merged program's code springs alive!.

对于还没有准备好进入黄金时段的新流程，或者在发布之前不能在代码中活动的新流程，您可能还想使用声明式。

总之，我就是这么做的。

对Tod Thomson的答案稍加修改(私生子化?)，将其作为一个静态函数而不是一个单独的类(我希望能够从我已经包含的viewutils类中调用它)。

public static bool isDebugging() {
    bool debugging = false;

    WellAreWe(ref debugging);

    return debugging;
}

[Conditional("DEBUG")]
private static void WellAreWe(ref bool debugging)
{
    debugging = true;
}

我得想个更好的办法。我明白了，#if块是其他配置中的有效注释(假设DEBUG或RELEASE;但任何符号都适用)

public class Mytest
    {
        public DateTime DateAndTimeOfTransaction;
    }

    public void ProcessCommand(Mytest Command)
        {
            CheckMyCommandPreconditions(Command);
            // do more stuff with Command...
        }

        [Conditional("DEBUG")]
        private static void CheckMyCommandPreconditions(Mytest Command)
        {
            if (Command.DateAndTimeOfTransaction > DateTime.Now)
                throw new InvalidOperationException("DateTime expected to be in the past");
        }

默认情况下，如果项目在调试模式下编译，Visual Studio定义DEBUG，如果项目在发布模式下编译，则不定义DEBUG。默认情况下，RELEASE模式中没有定义RELEASE。可以这样说:

#if DEBUG
  // debug stuff goes here
#else
  // release stuff goes here
#endif

如果你只想在发布模式下做某事:

#if !DEBUG
  // release...
#endif

此外，值得指出的是，您可以在返回void的方法上使用[Conditional("DEBUG")]属性，以便仅在定义了某个符号时执行它们。如果符号没有定义，编译器将删除对这些方法的所有调用:

[Conditional("DEBUG")]
void PrintLog() {
    Console.WriteLine("Debug info");
}

void Test() {
    PrintLog();
}

一个可以为您节省大量时间的技巧-不要忘记，即使您在构建配置下选择了调试(在vs2012/13菜单中，它在build => configuration MANAGER下)-这是不够的。

你需要注意PUBLISH配置，比如:

确保在“项目生成属性”中定义了DEBUG常量。这将启用#if DEBUG。我没有看到预定义的RELEASE常量，所以这可能意味着任何不在DEBUG块中的东西都是RELEASE模式。