如何将enum作为参数传递给目标c中的函数

Question

头文件如下所示：

enum RatingsEnum
{
    userRating,
    criticRating,
};

@interface SFMovie : NSObject

- (NSNumber *)getRating:(NSDictionary *)movieDic :(enum RatingsEnum) rating;

@end

如何使用此方法getRating？我不知道如何通过枚举。我的主叫代码：

- (void) testGetCriticRatingMethod{

    NSMutableDictionary *ratingDictionary = [[NSMutableDictionary alloc]init];
    [ratingDictionary setObject:@"Certified Fresh" forKey:@"critics_rating"];
    [ratingDictionary setObject:@"70" forKey:@"critics_score"];
    [ratingDictionary setObject:@"Certified Fresh" forKey:@"audience_rating"];
    [ratingDictionary setObject:@"87" forKey:@"audience_score"];
    SFMovie *movie = [[SFMovie alloc]init];
    enum RatingsEnum ratings;
    NSInteger userRating = [movie getRating:ratingDictionary rating:userRating];
}

这会产生以下警告： 'SFMovie'没有可见的@interface声明选择器'getRating：rating：'

有人可以指导我一个好的enum教程吗？谢谢大家。

Answer 1

更改

 - (NSNumber *)getRating:(NSDictionary *)movieDic :(enum RatingsEnum) rating;

到

 - (NSNumber *)getRatingWithDictionary:(NSDictionary *)movieDic ratingEnum:(enum RatingsEnum) ratingEnum;

更改

 enum RatingsEnum ratings;
 NSInteger userRating = [movie getRating:ratingDictionary rating:userRating];

到

 enum RatingsEnum ratings = userRating;
 NSNumber *ratingFromUser = [movie getRatingWithDictionary:ratingDictionary ratingEnum:ratings];

Answer 2

这与enum或参数的类型完全无关。你的语法完全错了。声明的方法名称为getRating::。正确的通话看起来像

[movie getRating:ratingDictionary :userRating];

为第二个参数添加标签

- (NSNumber *)getRating:(NSDictionary *)movieDic ofType:(enum RatingsEnum)rating;