从iOS中的阵列中复制以及原始项目

Question

我有一个数组，as

(约翰，简，约翰(

我想获得重复以及数组的原始元素，例如

(约翰，约翰(我可以从代码中获得单一的事件这里

NSArray *names = [NSArray arrayWithObjects:@"John", @"Jane", @"John", nil];
NSCountedSet *set = [[NSCountedSet alloc] initWithArray:names];
for (id item in set)
{
    NSLog(@"Name=%@, Count=%lu", item, (unsigned long)[set countForObject:item]);
    if((unsigned long)[set countForObject:item]>1){
        NSLog(@"of repeated element-----=%@",item);
    }
} 

"重复元素的名称-----约翰"，但我希望所有重复元素的出现，例如"重复元素的名称------约翰，约翰"。

Answer 1

尝试使用nspredicate ：

尝试此

NSArray *array = [NSArray arrayWithObjects:@"John", @"Jane", @"John",@"Jane",@"Jane", nil];
NSMutableArray *arrResult = [[NSMutableArray alloc] init];
NSCountedSet *set = [[NSCountedSet alloc] initWithArray:array];
for(id name in set)
   {
        if([set countForObject:name] > 1 ){
            NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF = %@", name];
            [arrResult addObjectsFromArray:[array filteredArrayUsingPredicate:predicate]];
        }
    }
    //
    NSLog(@"%@",arrResult);

Answer 2

我不确定您的最终目的，您想要的结果看起来毫无意义。无论如何，出于学习目的，以下是实施;(

NSArray *names = [NSArray arrayWithObjects:@"John", @"Jane", @"John", nil];
NSMutableDictionary *countDict = [NSMutableDictionary dictionary];
for (NSString *name in names) {
    if (countDict[name] == nil) {
        countDict[name] = [NSMutableString stringWithString:name];
    }
    else{
        NSMutableString *repeatedName = (NSMutableString *)countDict[name];
        [repeatedName appendString:@","];
        [repeatedName appendString:name];
    }
}
[countDict enumerateKeysAndObjectsUsingBlock:^(NSString *_Nonnull name, NSString * _Nonnull repeatedNames, BOOL * _Nonnull stop) {
    if (repeatedNames.length > name.length) {
        NSLog(@"Name of repeated element-----%@",repeatedNames);
    }
}];

输出：重复元素的名称-----约翰，约翰

Answer 3

使用loop

尝试此代码

NSArray *names = [NSArray arrayWithObjects:@"John", @"Jane", @"John",@"John", nil];
        NSCountedSet *set = [[NSCountedSet alloc] initWithArray:names];
        NSMutableArray *repeatedArray = [[NSMutableArray alloc] init];
        for (id item in set)
        {
            NSLog(@"Name=%@, Count=%lu", item, (unsigned long)[set countForObject:item]);
            if((unsigned long)[set countForObject:item]>1){
                NSLog(@"of repeated element-----=%@",item);
                for(int i=0;i<[set countForObject:item];i++)
                 {
                    [repeatedArray addObject:item];
                 }
        }

输出：约翰，约翰，约翰