iphone - 对数组中的多个值进行排序

Question

我有一个数组，其中包含针对不同状态的多个位置。

{"location":"Lekki Phase 1","state":"abc","country":"Nigeria"},
{"location":"Lekki Phase 2","state":"xyz","country":"Nigeria"},
{"location":"Osapa London1","state":"def","country":"Nigeria"},
{"location":"Lekki Phase 2","state":"abc","country":"Nigeria"},
{"location":"Lekki Phase 3","state":"xyz","country":"Nigeria"},
{"location":"Osapa London 2","state":"def","country":"Nigeria"},..........

现在我可以为没有重复状态的不同状态制作一个数组，例如

 {"abc","xyz","def"}

但是我想要的是在表格中明智地显示所有位置。

我怎样才能做到这一点？？

Answer 1

使用NSPredicate我们可以有效地过滤此。我已经尝试过并为我工作。

这里的“allDataArray”是带有字典的数组，您可以在此处替换您的数组(帖子中的第一个)

    NSMutableArray *allDataArray = [[NSMutableArray alloc] init];
    NSMutableDictionary *dict1 = [[NSMutableDictionary alloc] init];
    [dict1 setObject:@"Lekki Phase 1" forKey:@"location"];
    [dict1 setObject:@"abc" forKey:@"state"];
    [dict1 setObject:@"Nigeria" forKey:@"country"];
    [allDataArray addObject:dict1];

    dict1 = [[NSMutableDictionary alloc] init];
    [dict1 setObject:@"Lekki Phase 2" forKey:@"location"];
    [dict1 setObject:@"xyz" forKey:@"state"];
    [dict1 setObject:@"Nigeria" forKey:@"country"];
    [allDataArray addObject:dict1];

    dict1 = [[NSMutableDictionary alloc] init];
    [dict1 setObject:@"Lekki Phase 2" forKey:@"location"];
    [dict1 setObject:@"abc" forKey:@"state"];
    [dict1 setObject:@"Nigeria" forKey:@"country"];
    [allDataArray addObject:dict1];

    dict1 = [[NSMutableDictionary alloc] init];
    [dict1 setObject:@"Lekki Phase 3" forKey:@"location"];
    [dict1 setObject:@"xyz" forKey:@"state"];
    [dict1 setObject:@"Nigeria" forKey:@"country"];
    [allDataArray addObject:dict1];
    //NSLog(@"%@",allDataArray);

    NSArray *state = [NSArray arrayWithObjects:@"abc",@"xyz", nil];

    NSMutableArray *locationInState = [[NSMutableArray alloc] initWithCapacity:[state count]];
    for(int i=0; i< [state count]; i++)
    {
        NSMutableArray *filteredarray = [[allDataArray filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"(state == %@)", [state objectAtIndex:i]]] mutableCopy];
        for(int j=0; j<[filteredarray count];j++)
        {
            NSDictionary *dict = [filteredarray objectAtIndex:j];
            [filteredarray replaceObjectAtIndex:j withObject:[dict valueForKey:@"location"]];
        }
        [locationInState addObject:filteredarray];
    }
    NSLog(@"%@",locationInState);

这里locationInState数组包含文件状态的所有位置。您可以轻松地按索引映射它们。

结果是

(
    (
        "Lekki Phase 1",
        "Lekki Phase 2"
    ),
        (
        "Lekki Phase 2",
        "Lekki Phase 3"
    )
)