iphone - 从 NSDictionary 获取对象的麻烦

Question

我正在制作带有 2 个数组的字典，一个用于键（您可以在 Dic 中看到的 ID）和一个用于值（您可以在 Dic 中看到的出生日期）我的字典看起来像这样

100000297621293 = "08/31/1990";
100001904155266 = "12/30/1990";
100003248631105 = "05/27/1990";
100004327360299 = "01/01/1927";
100000157646688 = "08/22/1989";
100001069796883 = "12/03/1989";
100001475514001 = "03/09/1990";
100000717474427 = "08/05/1990";
100001221367192 = "08/05/1990";
100002586744158 = "04/15/1983";

这只是样本 dic 不完整

然后在我有另一个带有 ids 的数组并且我使用该数组从这个 Dic 获取出生日期但我得到空值请帮助我之后，我的代码如下

注意：我用于键的数组在 DIC 中始终作为键存在

NSDictionary *birthdayDictionary = 
[[NSDictionary alloc] initWithObjects:_parssedArrayOfFaceBook forKeys:_parssedArrayOfFaceBookUid];

NSLog(@"asdas%@",birthdayDictionary.description);

NSMutableArray *matches = [NSMutableArray array];

for (NSString *key in _selecteduid) {
    NSLog(@" see it%@",key);
    NSString *selectedBirthDate = [birthdayDictionary objectForKey:key];
    NSLog(@" matched%@",selectedBirthDate);
    [matches addObject:selectedBirthDate];
    NSLog(@" matched%@",matches);

}

Answer 1

假设 selecteduid 是一个保留属性并且其中包含值，则此代码可以正常工作。

NSDictionary *birthdayDictionary = [NSDictionary dictionaryWithObjects:self.parssedArrayOfFaceBook
                                                                   forKeys:self.parssedArrayOfFaceBookUid];
    NSMutableArray *matches = [@[] mutableCopy];

    for (NSString *key in self.selecteduid){
        NSString *selectedBirthDate = birthdayDictionary[key];
        [matches addObject:selectedBirthDate];
    }

Answer 2

为什么是*selectedBirthDate一个NSMutableArray？出生日期（值）是字符串！不是数组！

NSString *selectedBirthDate = [birthdayDictionary objectForKey:key];