Question

我正在尝试过滤一系列频道＆＃39;只找到类型属性为Twitter＆＃39; Twitter＆＃39;。但是，我尝试使用NSPredicate过滤数组会返回一个空数组。这是我的代码：

NSMutableDictionary *officials = [decodedData valueForKey:@"officials"];
NSMutableArray *channels = [officials valueForKey:@"channels"];
NSLog(@"%@", channels);


NSPredicate *twitterPredicate = [NSPredicate predicateWithFormat:@"type = 'Twitter'"];
NSLog(@"%@", [channels filteredArrayUsingPredicate:twitterPredicate]);

这是我在应用谓词之前和之后的回报：

在：

 (
    (
            {
        id = SenatorFeinstein;
        type = Facebook;
    },
            {
        id = SenFeinstein;
        type = Twitter;
    },
            {
        id = SenatorFeinstein;
        type = YouTube;
    }
),
    (
            {
        id = senatorboxer;
        type = Facebook;
    },
            {
        id = SenatorBoxer;
        type = Twitter;
    },
            {
        id = SenatorBoxer;
        type = YouTube;
    }
),

）

后：

2015-01-07 10:19:31.760 voices[537:66850] ()

我的谓词过滤器有问题吗？我正在使用适用于iOS的Google Civic API。任何建议表示赞赏

Answer 1

试试这个，它从通道数组中的数组中得到你所有的dict：

NSMutableDictionary *officials =[decodedData valueForKey:@"officials"];
NSMutableArray *channels = [officials valueForKey:@"channels"];
NSLog(@"%@", channels);

NSMutableArray *onlyChannels = [[NSMutableArray alloc] init];
for (NSArray *array in channels)
{
    for (NSDictionary  *dict in array)
    {
        [onlyChannels addObject:dict];
    }
}


NSPredicate *twitterPredicate = [NSPredicate predicateWithFormat:@"type = 'Twitter'"];
NSLog(@"%@", [onlyChannels filteredArrayUsingPredicate:twitterPredicate]);

NSPredicate返回空数组

1 个答案: