Obj-C 中的多值枚举

在Objective-C中，多值枚举是一种非常方便的数据类型，它允许我们在一次操作中同时传递多个选项或标志位。这种枚举类型可以用于定义一个包含多个值的集合，每个值都可以通过按位或运算符进行组合。本文将介绍Obj-C中的多值枚举的用法，并通过一个案例代码来说明其实际应用。

objc
typedef NS_OPTIONS(NSUInteger, MyOptions) {
    MyOptionNone      = 0,
    MyOptionOption1   = 1 << 0,  // 1
    MyOptionOption2   = 1 << 1,  // 2
    MyOptionOption3   = 1 << 2,  // 4
    MyOptionOption4   = 1 << 3   // 8
};

objc
- (void)processOptions:(MyOptions)options {
    if (options & MyOptionOption1) {
        NSLog(@"Option 1 is selected");
    }
    
    if (options & MyOptionOption2) {
        NSLog(@"Option 2 is selected");
    }
    
    if (options & MyOptionOption3) {
        NSLog(@"Option 3 is selected");
    }
    
    if (options & MyOptionOption4) {
        NSLog(@"Option 4 is selected");
    }
}

objc
typedef NS_OPTIONS(NSUInteger, MyOptions) {
    MyOptionNone      = 0,
    MyOptionOption1   = 1 << 0,  // 1
    MyOptionOption2   = 1 << 1,  // 2
    MyOptionOption3   = 1 << 2,  // 4
    MyOptionOption4   = 1 << 3   // 8
};
- (void)processOptions:(MyOptions)options {
    if (options & MyOptionOption1) {
        NSLog(@"Option 1 is selected");
    }
    
    if (options & MyOptionOption2) {
        NSLog(@"Option 2 is selected");
    }
    
    if (options & MyOptionOption3) {
        NSLog(@"Option 3 is selected");
    }
    
    if (options & MyOptionOption4) {
        NSLog(@"Option 4 is selected");
    }
}
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        MyOptions selectedOptions = MyOptionOption1 | MyOptionOption3 | MyOptionOption4;
        [self processOptions:selectedOptions];
    }
    return 0;
}