Question

我有这样的数组数据。

  animals = @[@"Bear", @"Black Swan", @"Buffalo", @"Camel", @"Cockatoo", @"Dog", @"Donkey", @"Emu", @"Giraffe", @"Greater Rhea", @"Hippopotamus", @"Horse", @"Koala", @"Lion", @"Llama", @"Manatus", @"Meerkat", @"Panda", @"Peacock", @"Pig", @"Platypus", @"Polar Bear", @"Rhinoceros", @"Seagull", @"Tasmania Devil", @"Whale", @"Whale Shark", @"Wombat"];

以及如何通过首字母分组到nsmutabledictionary。（取决于数组数据）就像这样。

 animals = @{@"B" : @[@"Bear", @"Black Swan", @"Buffalo"],
            @"C" : @[@"Camel", @"Cockatoo"],
            @"D" : @[@"Dog", @"Donkey"],
            @"E" : @[@"Emu"],
            @"G" : @[@"Giraffe", @"Greater Rhea"],
            @"H" : @[@"Hippopotamus", @"Horse"],
            @"K" : @[@"Koala"],
            @"L" : @[@"Lion", @"Llama"],
            @"M" : @[@"Manatus", @"Meerkat"],
            @"P" : @[@"Panda", @"Peacock", @"Pig", @"Platypus", @"Polar Bear"],
            @"R" : @[@"Rhinoceros"],
            @"S" : @[@"Seagull"],
            @"T" : @[@"Tasmania Devil"],
            @"W" : @[@"Whale", @"Whale Shark", @"Wombat"]};

谢谢。!!

Answer 1

自己很容易完成，但无论如何要检查这段代码

NSArray *words = @[@"AS", @"CS", @"AQ", @"CA", @"SA"];
NSMutableDictionary *dic = [NSMutableDictionary dictionary];
for (NSString *word in words) {

    if (word.length > 0) {

        NSString *firstChar = [word substringToIndex:1];
        NSMutableArray *contents = dic[firstChar];
        if (!contents) {
            contents = [NSMutableArray array];
            dic[firstChar] = contents;
        }

        [contents addObject:word];
    }


}

Answer 2

你需要自己做。迭代数组，从项中获取第一个字符，检查它是否存在于字典中，如果存在则添加到数组中，如果不存在则插入新数组。

任何替代方法都将使用提供此功能的第三方库。

Answer 3

NSArray *animals = @[@"Bear", @"Black Swan", @"Buffalo", @"Camel", @"Cockatoo", @"Dog", @"Donkey", @"Emu", @"Giraffe", @"Greater Rhea", @"Hippopotamus", @"Horse", @"Koala", @"Lion", @"Llama", @"Manatus", @"Meerkat", @"Panda", @"Peacock", @"Pig", @"Platypus", @"Polar Bear", @"Rhinoceros", @"Seagull", @"Tasmania Devil", @"Whale", @"Whale Shark", @"Wombat"];

NSMutableDictionary *animalDict = [NSMutableDictionary dictionary];

for (NSString *animal in animals) {
    NSString *firstLetter = [animal substringToIndex:1];
    NSMutableArray *letterArray = [animalDict objectForKey:firstLetter];
    if (!letterArray) {
        letterArray = [NSMutableArray arrayWithObject:animal];
        [animalDict setObject:letterArray forKey:firstLetter];
    } else {
        [letterArray addObject:animal];
        [letterArray sortUsingSelector:@selector(caseInsensitiveCompare:)];
    }
}

NSLog(@"%@", animalDict);

如何将数组中的数据拆分和排序为nsmutabledictionary

3 个答案: