Question

In my app I have a NSError that I declare locally:

NSError *error;

Do I release it in dealloc method or do I need to release it in the method I declare it?

Answer 1

Please read the Cocoa Memory Management Guide, memory management is something you should understand perfectly. (And it’s not hard.) If you declare a variable in a method, you don’t have a pointer to it in dealloc, therefore you can’t release it there – you can only release it before it goes out of scope. Another question is if you should release it at all. That depends on whether it is a stack-based, autoreleased or retained variable:

float foo[] = {1, 2, 3}; // stack-based, no releasing necessary
NSString *foo = [NSString stringWithFormat:…]; // autoreleased, you must not release it
NSString *foo = [[NSString alloc] initWith…]; // retained, you must release it