ios中文件模式的枚举定义

[Cpp肥兔]

enum _Openmode
{ // constants for file opening options
_Openmask = 0xff};

static const _Openmode in = (_Openmode)0x01;
static const _Openmode out = (_Openmode)0x02;
static const _Openmode ate = (_Openmode)0x04;
static const _Openmode app = (_Openmode)0x08;
static const _Openmode trunc = (_Openmode)0x10;
static const _Openmode _Nocreate = (_Openmode)_IOS_Nocreate;
static const _Openmode _Noreplace = (_Openmode)_IOS_Noreplace;
static const _Openmode binary = (_Openmode)_IOSbinary;

这是在标准c++头文件中看到的对于文件流模式的定义，定义于ios类中
这样的枚举写法，小弟还真没见到过，请大侠们给指点指点

[彩阳]

多看看这样的代码，不久你就会知道的。枚举其实也是一个类型，和class和namespace是同一个级别的。_Openmode是枚举名。这里用到了很多的常量，在VC中选择转到定义就可以查看到其实都是一系列十六进制码。

[hongwenjun]

/*颜色参数直接使用 
White_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE); 
Red_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_RED); 
Green_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_GREEN); 
Yellow_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_RED | FOREGROUND_GREEN); 
Blue_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_BLUE); 
Magenta_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_RED | FOREGROUND_BLUE); 
Cyan_Black: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY | 
                        FOREGROUND_GREEN | FOREGROUND_BLUE); 
Black_Gray: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),BACKGROUND_INTENSITY | 
                        BACKGROUND_INTENSITY); 
Black_White: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),BACKGROUND_INTENSITY | 
                        FOREGROUND_INTENSITY | BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE); 
Red_White: 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),BACKGROUND_INTENSITY | 
                        FOREGROUND_INTENSITY | BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE | 
                        FOREGROUND_RED); 
*/  

通过上面这个图和代码能否看懂

[qscool1987]

在VC中很多这样的定义，比如说窗口样式，属性页按钮风格设置，这样通过 | 操作可能将两个不同的功能进行组合，满足不同的需求
static const _Openmode in = (_Openmode)0x01;
至于这句的意思就是定义一个静态的枚举常量in