removing duplicates in nsarray

Question

Hi friends

how can i remove duplicates in nsarray. for instance my array contains following data. I want to compare with adjacent dates to avoid duplicates but it throughs error.

Can anyone guide me what i am going wrong

calendar first-

( 2010-09-25 17:00:00 GMT,

"AAA",
2010-09-25 17:00:00 GMT,
"AAA",
2010-09-26 17:00:00 GMT,
"BBB",
2010-09-26 17:00:00 GMT,
"BBB",
2010-09-27 17:00:00 GMT,
"CCCC",
2010-09-27 17:00:00 GMT,
"CCC",
2010-09-28 17:00:00 GMT,
"AAA",
2010-09-28 17:00:00 GMT,
"AAA",
2010-09-29 17:00:00 GMT,
"DDDD",
2010-09-29 17:00:00 GMT,
"DDDD",
2010-09-30 17:00:00 GMT,
"BBBB"
)

my code

NSArray dates; //dates contain above values

NSMutableArray *temp_date = [[NSMutableArray alloc] init];


for (int i=0; i<[dates count]; i+=2){
    BOOL day;


    if ([dates count]-2 >i) {


        day = [[dates objectAtIndex:i] compare:[dates objectAtIndex:i+2]];


    }   


    if (day) {
        [temp_date addObject:[dates objectAtIndex:i]];
        [temp_date addObject:[dates objectAtIndex:i+1] ];

    }



}

Regards, sathish

Answer 1

To find identical objects you should better use –indexOfObjectIdenticalTo: or –indexOfObjectIdenticalTo:inRange:

Answer 2

You could use sets. Duplicates will be removed automatically upon creation.

NSArray *cleanedArray = [[NSSet setWithArray:dates] allObjects];

Bear in mind that a set is unordered.

Answer 3

u could use isEqual method of NSObject . which compare the object content equality.