將NSArray轉換為NSDictionary以進行分段

Question

我有這個NSArray：

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

而且我想在UITableView中創建部分，所以我需要像這樣的字典：

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

您能幫我告訴我怎么做嗎？ 謝謝。

這是我添加數組的方式：

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

更新

現在，我看到您想要的是Animal類型的對象，而不是NSDictionary類型的對象。 這行代碼是animal[@"name"]需要使用任何訪問方法來獲取該名稱。 我更新了代碼，以為您需要animal.name 。

您是否要一個完整的索引（即使大多數鍵都有一個空數組，字典也要具有所有值“ A”-“ Z”）？

- (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（僅包含具有值的鍵的字典）？

- (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 *
}

---

作為第二次更新，有些奇怪。

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

正在講故事Animal *在animalArray ，但是出現的錯誤消息似乎表明NSMutuableArray *對象存儲在animalArray 。

Answer 2

嘗試下面的代碼。

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] ;
    }
    }

您可以通過allKeysArray計數來設置節數，如下所示

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

希望它可以幫助您...！

Answer 3

希望下面是您正在尋找的代碼。

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是通過分組獲得的新詞典。 [dictionaryWithSections allKeys]將返回您想要的所有節標題。 即L，C ..等

Answer 4

拿字典並為鍵設置對象

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