Question

我需要将NSString变量与存储在NSMutableArray中的NSDictionary中的对象进行比较

我的NSMutableArray包含每个都有两个NSString对象的Manu NSDictionaries

在我向数组添加更多内容之前，我想确保它不在那里，但在那时我只知道其中一个对象名称

例如

NSDictionary持有@＆＃34; foo＆＃34;对于关键@＆＃34; bar＆＃34;和@＆＃34; Jongel＆＃34;关键@＆＃34; fibbel＆＃34;

现在我想构建并在数组中插入一个新的NSDictionary，但仅限于NSString @＆＃34; foo＆＃34;不在数组内的dict里面

我找不到任何文档如何在数组中处理NSDictionary，我可以找到文档如何使用NSArray * myArray = dict [0]在nsdictionary中查找数组然后循环，但这就是我需要的东西走另一条路

如何做到这一点？

这是我正在尝试但我无法正确的

+ (void) splitOutCategories:(NSMutableArray *)reveProducts {
    if([NWTillHelper isDebug] == 1) {
        NSLog(@"%s entered with array count = %lu", __PRETTY_FUNCTION__, reveProducts.count);
    }

    NSMutableArray *reveCollections = [[NSMutableArray alloc] init];

    for (NSDictionary *dictProduct in reveProducts) {
        NSMutableDictionary *dictReveCollections = [[NSMutableDictionary alloc] init];
        NSArray *arrLocales = dictProduct[@"locales"];
        for (NSDictionary *dictLocale in arrLocales) {
            NSArray *arrCategories = dictLocale[@"categories"];
            NSArray *arrImages = dictLocale[@"images"];
            if(arrCategories.count < 1) {
                // Nothing to do
            } else if (arrCategories.count == 1) {
                if(![reveCollections containsObject:arrCategories[0]]) {
                    // Here we need to build the entire dict and insert into the array
                    NSString *fcTitle = arrCategories[0];
                    NSString *fcImageUrl = arrImages[0];
                    [dictReveCollections setObject:fcTitle forKey:@"fcTitle"];
                    [dictReveCollections setObject:fcImageUrl forKey:@"fcImageUrl"];
                    [reveCollections addObject:dictReveCollections];
                }
            } else if (arrCategories.count > 1) {
                if(![reveCollections containsObject:arrCategories[1]]) {
                    NSString *fcTitle = arrCategories[1];
                    NSString *fcImageUrl = nil;
                    if(arrImages.count < 1) {
                        fcImageUrl = @"https://xxxxyyyyy.png";
                    } else {
                        fcImageUrl = arrImages[0];
                    }
                    [dictReveCollections setObject:fcTitle forKey:@"fcTitle"];
                    [dictReveCollections setObject:fcImageUrl forKey:@"fcImageUrl"];
                    [reveCollections addObject:dictReveCollections];
                }
            }
        }
    }
    NSLog(@"reveCollectionsArray = \r\n%@", reveCollections);
    NSLog(@"reveCollectionsArrayCount = %lu", reveCollections.count);
}

Answer 1

在向数组中添加更多整体之前，我想确保其尚未存在

这里的解决方案取决于确切需要唯一的内容。如您所述，这听起来像只有NSDictionary键/值对的值需要唯一（“ foo”，“ Jongel”）。如果是这种情况，那么您可以使用NSMutableSet跟踪您已经接受的值，从而轻松解决非常。

这样的方法会起作用：

@interface CollectionExample ()
@property (strong, nonatomic) NSMutableArray *reveCollections;
@property (strong, nonatomic) NSMutableSet *storedValues;
@end

@implementation CollectionExample

- (instancetype)init {
    self = [super init];
    if (self) {
        _storedValues = [NSMutableSet set];
        _reveCollections = [NSMutableArray array];
    }
    return self;
}

- (BOOL)valueAlreadyExists:(NSString *)newValue {
    return [self.storedValues containsObject:newValue];
}

- (void)addNewKeyValuePair:(NSString *)key value:(NSString *)value {
    if ([self valueAlreadyExists:value]) {
        // handle this however you'd like
        return;
    }
    NSDictionary *dict = @{key: value};
    [self.reveCollections addObject:dict];
    [self.storedValues insertObject:value];
}

@end

但是，如果唯一的键/值对是唯一的，则必须遍历数组，并遍历数组中的每个键/值对每个字典。这样的事情应该起作用：

- (BOOL)valueAlreadyExists:(NSString *)newKey value:(NSString *)newValue {
    BOOL foundPair = NO;
    for (NSDictionary *dict in self.reveCollections) {
        [dict enumerateKeysAndObjectsUsingBlock:^(id  _Nonnull key, id  _Nonnull obj, BOOL * _Nonnull stop) {
            if ([newKey isEqualToString:key] && [newValue isEqualToString:obj]) {
                foundPair = YES;
                *stop = YES;
                return;
            }
        }];
    }
    return foundPair;
}

如何将变量与NSArray内部的NSDictionary内的对象进行比较？

1 个答案: