如何连接__NSCFArray的对象？

Question

我正在从Yelp获取数据，我得到了

NSLog(@"categories:%@", categories);
NSLog(@"categories: %@", [categories class]);
NSLog(@"categories: %@", [categories componentsJoinedByString:@","]);

我把日志看作是

    categories:(
        (
        Thai,
        thai
    )
)
2014-06-19 16:20:47.338 yelp[28929:70b] categories class: __NSCFArray
2014-06-19 16:20:47.341 yelp[28929:70b] categories:(
        (
        Thai,
        thai
    )
)
2014-06-19 16:20:47.341 yelp[28929:70b] categories class: __NSCFArray
2014-06-19 16:20:47.343 yelp[28929:70b] categories:(
        (
        Thai,
        thai
    )
)
2014-06-19 16:20:47.343 yelp[28929:70b] categories class: __NSCFArray

所以很明显，componentsJoinedByString不会加入其中。

作为一个新手，我想知道如何加入__NSCFArray的项目

Answer 1

根据rmaddy的建议，我观察到了什么是不正确的。

这对我很管用

NSString *categoriesJoined = [(business[@"categories"][0]) componentsJoinedByString:@","];