ios - 按日期用字典对数组进行排序

Question

我有一个 NSArray，里面有 NSDictionary。看起来像:

等等

我需要在 NSDictionary 中按日期对其进行排序。我需要这样的东西:

我该怎么做？这是我的方法，它为我提供了第一个未排序的数组:

- (void)iterateOverDocumentsDirectory
{
    arrayWithFiles = [NSMutableArray new];

    NSFileManager *fileManager = [[NSFileManager alloc] init];
    NSError *error;

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirPath = [paths objectAtIndex:0];

    NSString *finalPathToFolder = [NSString stringWithFormat:@"%@/", documentsDirPath];

    albumNames = [[fileManager contentsOfDirectoryAtPath:finalPathToFolder error:&error] mutableCopy];
    if (albumNames == nil) {
        // error...
    }

    for (NSString *album in albumNames)
    {
        NSMutableDictionary *tempDict = [[NSMutableDictionary alloc] init];
        [tempDict setValue:album forKey:@"name"];

        NSString *finalPathToFiles = [NSString stringWithFormat:@"%@/%@", documentsDirPath, album];

        NSArray *tempArray = [fileManager contentsOfDirectoryAtPath:finalPathToFiles error:&error];

        NSMutableArray *arrayWithEachFiles = [NSMutableArray new];
        for (NSString *tempString in tempArray)
        {
            NSMutableDictionary *eachFileDict = [[NSMutableDictionary alloc] init];
            NSString *pathToFile = [NSString stringWithFormat:@"%@/%@/%@", documentsDirPath, album, tempString];

            [eachFileDict setValue:pathToFile forKey:@"path"];

            NSDictionary *filePathsArray1 = [[NSFileManager defaultManager] attributesOfItemAtPath:pathToFile error:nil];
            NSDate *modifiedDate = [filePathsArray1 objectForKey:NSFileCreationDate];

            [eachFileDict setValue:modifiedDate forKey:@"date"];

            [arrayWithEachFiles addObject:eachFileDict];
        }

        NSSortDescriptor *ageDescriptor = [[NSSortDescriptor alloc] initWithKey:@"date" ascending:YES];
        NSArray *sortDescriptors = @[ageDescriptor];
        NSArray *sortedArrayWithFiles = [[arrayWithEachFiles sortedArrayUsingDescriptors:sortDescriptors] mutableCopy];

        [tempDict setValue:sortedArrayWithFiles forKey:@"files"];

        [arrayWithFiles addObject:tempDict];
    }
}

Answer 1

使用以下代码对字典数组进行排序:

NSArray * sortedArray = [myArray sortedArrayUsingComparator:^(id obj1, id obj2) {
            NSNumber *rating1 = [(NSDictionary *)obj1 objectForKey:@"date"];
            NSNumber *rating2 = [(NSDictionary *)obj2 objectForKey:@"date"];
            return [rating1 compare:rating2];
        }];