yong ho yong ho - 4 months ago 13
Objective-C Question

How to remove duplicate of objects that has same value from NSArray

I have an

look like this:

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

How to remove the ditionaries which have the same name. For example, I want to remove the duplicate "a" and "c". I want the result to be like this:

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


Just use following code for remove duplicates values.

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

You have to just call groupsWithDuplicatesRemoved this method with key name.

- (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 =[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;

Hope, this is what you're looking for. Any concern get back to me. :)