What's the difference between NSNumber and NSInteger?

iphone objective-c nsnumber primitive-types nsinteger
mk12 picture mk12 · Aug 16, 2009 · Viewed 59.7k times · Source

What's the difference between NSNumber and NSInteger? Are there more primitives like these that I should know about? Is there one for floats?

Answer

iKenndac picture iKenndac · Aug 16, 2009

NSNumber is a class, not a primitive, and is used when you need to put raw numbers into dictionaries, arrays, or otherwise encapsulate them. NSInteger, NSUInteger, CGFloat, etc are simple types and correspond (on 32-bt systems like the iPhone) to int, unsigned int and float.

As a general rule, if you need to store a number somewhere, use NSNumber. If you're doing calculations, loops, etc, use NSInteger, NSUInteger or CGFloat.

You can wrap an NSInteger into an NSNumber:

NSNumber *aNumber = [NSNumber numberWithInteger:21];

... and get it back:

NSInteger anInteger = [aNumber integerValue];

You can find out more info here: http://iosdevelopertips.com/cocoa/nsnumber-and-nsinteger.html

Related questions

NSString To NSNumber

So this problem has been perplexing me for way too long. I have a UIAlertView with a textField in it, and I need the value of the textField as an NSNumber. But everything I try gives me random strings of …

Read More
Objective-C: Find numbers in string

I have a string that contains words as well as a number. How can I extract that number from the string? NSString *str = @"This is my string. #1234"; I would like to be able to strip out 1234 as an int. The …

Read More
check if NSNumber is empty

How do I check if a NSNumber object is nil or empty? OK nil is easy: NSNumber *myNumber; if (myNumber == nil) doSomething But if the object has been created, but there is no value in it because an assignment failed, …

Read More