Objective-C Difference between setting nil and releasing

Question

I\'ve learned that in dealloc you do [object release]; but in viewDidUnload (in a UIViewController subclass) you do self.object

Answer 1

If you do [object release], and want to access the object the app simply crash. If you do object = nil, and want to access the object nothing will perform.

The reason is in the [object release], you are attempted to free the object. so its dont have any pointer (no memoty).In the object = nil, you are attempted to assign the object with null pointer. so if u trying to access the object nothing will happen.

Generally we wrote the code as [object release]; object = nil; because if u access the object unexpectedly, the app wont crashed.