Size of an NSArray

int size = [array count];NSLog(@"there are %d objects in the array", size);

An answer to another answer:

You can't get the size of the array in megabytes, at least not without doing some tricky, unsupported* C voodoo. NSArray is a class cluster, which means we don't know how it's implemented internally. Indeed, the implementation used can change depending on how many items are in the array. Moreover, the size of the array is disjoint from the size of the objects the array references, since those objects live elsewhere on the heap. Even the structure that holds the object pointers isn't technically "part" of the array, since it isn't necessarily calloc'd right next to the actual NSArray on the heap.

If you want the size of the array struct itself, well that's apparently only 4 bytes:

NSLog(@"Size: %d", sizeof(NSArray));

Prints:

2010-03-24 20:08:33.334 EmptyFoundation[90062:a0f] Size: 4

(Granted, that's not a decent representation, since NSArray is probably just an abstract interface for another kind of object, usually something like an NSCFArray. If you look in NSArray.h, you'll see that an NSArray has no instance variables. Pretty weird for something that's supposed to hold other objects, eh?)

* By "unsupported" I mean "not recommended", "delving into the inner mysticism of class clusters", and "undocumented and private API, if it even exists"

Size can be determined by sending 'count' to the NSArray instance, and printing to console can be done via NSLog(), eg:

NSArray * array = [NSArray arrayWithObjects:@"one", @"two", @"three", nil];NSLog(@"array size is %d", [array count]);