Question

I want to SET items in an array in a dictionary.
I have an NSDictionary below, an instance called”currentCityNode”. In that Dictionary is an array item (amongst other things). The array item is called “TheConnections”
The code below successfully reads the array.

 NSArray *theConnectionsArray = [currentCityNode objectForKey:@"TheConnections"];
 (theConnectionsArray now contains the previously loaded values '3','7', and '9')

Now I want to set ONE of the values in this array. Make the second value ‘7’ a ‘5’.

I have tried a few variations, not able to get it yet.

[currentCityNode addObject:notsurewhattoputhere forKey:@"TheConnections"];

Answer 1

Your array and dictionary must be mutable and something like this should work. If theConnectionsArray is already mutable then you wont have to use mutableCopy.

NSMutableArray *theConnectionsArray = [[currentCityNode objectForKey:@"TheConnections"] mutableCopy];
[theConnectionsArray replaceObjectAtIndex:1 withObject:@"5"];
[currentCityNode setObject:theConnectionsArray forKey:@"TheConnections"];