Question

On page 326 in the book Programming in Objective-C 2.0 the author says:

myNumber = [[NSNumber alloc] initWithInt: 1000];  

Of course, based on previous discussions, if you create myNumber this way, you are re- sponsible for subsequently releasing it when you’re done using it with a statement such as follows:

[myNumber release];  

My question is:

Does this mean that if I create an NSNumber object with this statement

NSNumber *myNumber = [NSNumber numberWithInteger: 100];  

I don’t have to release the object myNumber myself?

Answer 1

This link is your bible

In the case of [NSNumber numberWithInt:] it returns an autoreleased object, and you don’t need to do anything to release it properly. Unless you retain it, of course, in which case you would call release on it, likely from your dealloc method.

[[NSNumber alloc] initWithInt:] returns an object with a retain count of one (from calling alloc). You are responsible for releasing any object created this way.