Question

i am getting unpredictable error when two of NSMutableArray having same value at index 0 then i want to remove that object and replace object with empty string. But app get crash saying

 -[__NSArrayI replaceObjectAtIndex:withObject:]: unrecognized selector sent to instance 0xe2a06b0
  2012-03-22 14:36:48.181 golf eScorer[3849:11f03] *** Terminating app due to uncaught exception  
  'NSInvalidArgumentException', reason: '-[__NSArrayI replaceObjectAtIndex:withObject:]: 
   unrecognized selector sent to instance 0xe2a06b0'  

When i debug using break point than log shows

2012-03-22 14:36:44.548 golf eScorer[3849:11f03] ArrayOfGameidOfPlayerToRemove....(
2
)
2012-03-22 14:36:44.549 golf eScorer[3849:11f03] discardedId...(
2
)

Here is my line of code:

 if([[ArrayOfGameidOfPlayerToRemove objectAtIndex:0] isEqualToString:[discardedId 
    objectAtIndex:0]])
        {
            [ArrayOfGameidOfPlayerToRemove replaceObjectAtIndex:0 withObject:emptyString];
        }

Update:

I solved like this

   NSMutableArray *ArrayOfGameidOfPlayerToRemove = [yournsarray mutableCopy];

Answer 1

It seems the variable ArrayOfGameidOfPlayerToRemove is instance of NSArray. You can replace object in only in NSMutableArray