Question

我有这个NSArray：

{name="LOBSTER",photo="prawn.jpg"},{name="COW", photo"cow_grass.png"},...so on

我想在UITableView中创建部分，所以我需要一个这样的字典：

{L=(name="Lobster";photo="prawn.jpg"),C=(name="COW"; photo="cow_grass.png"),...so on}

你可以帮我告诉我怎么做吗？谢谢。

这就是我添加数组的方式：

animalsArray = [[NSMutableArray alloc] init];
      //Loop through our JsonDict
      long countArray = [[dataDict valueForKey:@"animal"]count];
      for (int i = 0; i < countArray ; i++)
         {
         NSString * cName = [[[dataDict valueForKey:@"animal"]objectAtIndex:i]valueForKey: @"name"];
         NSString * cPhoto = [[[dataDict valueForKey:@"animal"]objectAtIndex:i]valueForKey: @"photo"];

         [animalArray addObject:[[Animals alloc]initWithName:cName andPhoto:cPhoto]];

Answer 1

<强>更新

我现在看到你想要一个Animal类型的对象而不是NSDictionary。代码行animal[@"name"]需要成为获取名称的访问器方法。我更新了我的代码，猜测你需要animal.name。

你想要一个完整的索引（包含所有值的词典＆＃39; A＆＃39; - ＆＃39; Z＆＃39;即使大多数键都有一个空数组）？

- (NSDictionary *)fullIndexOfAnimalsFromAnimals:(NSArray *)animals
{
    NSMutableDictionary *result = [NSMutableDictionary dictionary];

    // Create a key for each letter of the alphabet.
    for (char ch = 'A'; ch <= 'Z'; ++ch) {
        NSString *key = [NSString stringWithFormat:@"%c", ch];
        result[key] = [NSArray array];
    }

    // Add all the animals keyed by the first character of their name.
    for (Animal *animal in animals) {
        NSString *key = [animal.name substringToIndex:1] uppercaseString];
        result[key] = [result[key] arrayByAddingObject:animal];
    }

    return [result copy]; // NSMutableDictionary * to NSDictionary *
}

您是否需要部分索引（仅包含具有值的键的字典）？

- (NSDictionary *)partialIndexOfAnimalsFromAnimals:(NSArray *)animals
{
    NSMutableDictionary *result = [NSMutableDictionary dictionary];

    // Add all the animals keyed by the first character of their name.
    for (Animal *animal in animals) {
        NSString *key = [animal.name substringToIndex:1] uppercaseString];
        NSArray *value = result[key];
        if (value == nil) {
            result[key] = [NSArray arrayWithObject:animal]; // Create new array
        } else {
            result[key] = [value arrayByAddingObject:animal]; // Add to existing
        }
    }

    return [result copy]; // NSMutableDictionary * to NSDictionary *
}

作为第二次更新，有一些奇怪的事情。

[animalArray addObject:[[Animals alloc] initWithUser_id:cUser_id
                                                andName:cName
                                                 andNik:cNik
                                           andJob_title:cJob_title
                                               andPhone:cPhone
                                             andRoom_no:cRoom_no
                                               andPhoto:cPhoto]];

Animal *中的故事animalArray，但您的错误消息似乎表明NSMutuableArray *对象存储在animalArray中。

Answer 2

尝试以下代码..

NSMutableDictionary *finalResultDict=[NSMutableDictionary dictionary];

    for(NSDictionary *wildanimals in animalsarray)
    {

    NSString *key=[[wildanimals[@"name"] substringToIndex:1] uppercaseString];

    if([wildanimals[@"name"] hasPrefix:key])
    {
       [finalResultDict setValue: wildanimals forKey:key] ;
    }
    }

您可以通过allKeysArray计数设置部分数量，如下所示

NSArray * allKeysArray = [finalResultDict allKeys];
NSLog(@"Count : %d", [finalResultDict count]);

希望它可以帮助你......！

Answer 3

希望下面是您要查找的代码。

NSArray *currentArray = ...

// New dictionary object to hold the grouped results.
NSMutableDictionary *dictionaryWithSections = [NSMutableDictionary dictionary];

for (NSDictionary *dictionary in currentArray) {
    NSString *section = [[[dictionary objectForKey:@"name"] substringToIndex:1] uppercaseString];

    // Check whether section already exits.
    if ([dictionaryWithSections objectForKey:section]) {
        [[dictionaryWithSections objectForKey:section] addObject:dictionary];
    } else {
        NSMutableArray *sectionData = [NSMutableArray arrayWithObject:dictionary];
        [dictionaryWithSections setObject:sectionData forKey:section];
    }
}

dictionaryWithSections是您通过分组获得的新词典。 [dictionaryWithSections allKeys]将返回您想要的所有章节标题。即L，C ..等。

Answer 4

使用词典并设置对象

 NSMutableArray *arr;
NSMutableDictionary *dict=[[NSMutableDictionary alloc]init];
[dict setObject:arr forKey:@"L"];

将NSArray转换为NSDictionary进行切片

4 个答案: