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hiddenpremise
Feb 13, 2009, 09:35 AM
I have been able to use KVC to sum an array with objects that have an [NSNumber] as an instance variable. Can I sum just an array using KVC? My attempts so far have failed.
ie. This code will return an uncaught exception

NSArray *myArray = [NSArray arrayWithObjects:[NSNumber numberWithInt:5], [NSNumber numberWithInt:6], [NSNumber numberWithInt:7], nil];

NSLog(@"%@", [myArray valueForKeyPath:@"@sum"]);


I can easily sum an array of numbers using loops and several lines of code, but I am really trying to get a solid hold on KVC. Any help is appreciated :)

Thanks much,
-Whit



lee1210
Feb 13, 2009, 10:29 AM
I know nothing about KVC, but maybe this helps?
http://developer.apple.com/documentation/Cocoa/Conceptual/KeyValueCoding/Concepts/ArrayOperators.html#//apple_ref/doc/uid/20002176-178593

-Lee

Edit:
Looks like this will work:

NSLog(@"%@", [myArray valueForKeyPath:@"@sum.intValue"]);

MacRumors Guy
Feb 13, 2009, 10:40 AM
edit: delete plz