How do you store "int"
values in an NSMutableArray
or NSMutableDictionary
? Chronic problems with JSON data that come in as integers.
Should I try to store these integers as NSNumber
objects or just as strings that contain the integer?
How dangerous is it to do a "raw" (int) conversion on the pointers if I know the values will always be 开发者_如何学GoNatural Numbers (numbers>=0 including zero for null.)
The integers I'm always working with are Foreign Key Id's from a database.
Use NSNumber like this:
int yourInt = 5;
[myMutableArray addObject:[NSNumber numberWithInt:yourInt]];
Or using modern Objective C syntax, you can use the following for expressions:
[myMutableArray addObject:@(2 + 3)];
Or for lone numbers:
[myMutableArray addObject:@5];
Use NSNumber
objects (e.g. using [NSNumber numberWithInt:value]
)
You need to use NSNumber
, as others have said, or use an NSString
with the string representaton of the number. It really doesn't matter which, but the NSNumber
will be more efficient.
You can't just throw in an int
, let it be interpreted as a pointer, and then cast it back on the way out. The reason is that the object (that the int
will be interpreted as a pointer to) will be sent the retain
message when it is added to the array, and this will definately cause a crash since it will be an invalid pointer.
You can also use:
[myDict setObject:[NSNumber numberWithInt:anInteger] forKey:@"MyInteger"];
You can also add value like this
NSMutableArray *values = [NSMutableArray alloc]init];
[values addObject:[NSNumber numberWithInt:23]];
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