如何从 NSArray 中删除具有相同值的对象的重复项

Question

我的NSDictinary 看起来像这样：

NSArray *duplicates = @[@{@"name": @"a", @"id": @"123"}, @{@"name": @"c", @"id": @"234"}, @{@"name": @"a", @"id": @"431"}, @{@"name": @"c", @"id": @"983"}, @{@"name": @"a", @"038"}];

如何删除同名的词典。例如，我想删除重复的“a”和“c”。我希望结果是这样的：

NSArray *duplicates = @[@{@"name": @"a", @"id": @"123"}, @{@"name": @"c", @"id": @"234"}];

Answer 1

只需使用以下代码删除重复值。

your_array = [self groupsWithDuplicatesRemoved:(NSArray *)your_array myKeyParameter:@"your_key_name"];

你只需要用键名调用groupsWithDuplicatesRemoved这个方法。

- (NSMutableArray *) groupsWithDuplicatesRemoved:(NSArray *)  groups myKeyParameter:(NSString *)myKeyParameter {
    NSMutableArray * groupsFiltered = [[NSMutableArray alloc] init];    //This will be the array of groups you need
    NSMutableArray * groupNamesEncountered = [[NSMutableArray alloc] init]; //This is an array of group names seen so far

    NSString * name;        //Preallocation of group name
    for (NSDictionary * group in groups) {  //Iterate through all groups
        name = [NSString stringWithFormat:@"%@", [group objectForKey:myKeyParameter]]; //Get the group name
        if ([groupNamesEncountered indexOfObject: name]==NSNotFound) {  //Check if this group name hasn't been encountered before
            [groupNamesEncountered addObject:name]; //Now you've encountered it, so add it to the list of encountered names
            [groupsFiltered addObject:group];   //And add the group to the list, as this is the first time it's encountered
        }
    }
    return groupsFiltered;
}

希望，这就是您要找的。任何问题都可以回复我。 :)

Answer 2

你试过这个代码吗

NSArray *duplicates = @[@{@"name": @"a"}, @{@"name": @"c"}, @{@"name": @"a"}, @{@"name": @"c"}, @{@"name": @"a"}];
NSSet *set = [NSSet setWithArray:duplicates];
NSArray *uniqueArray = [set allObjects];