ios: 'release' is unavailable: not available in automatic reference counting mode [duplicate]

原文地址：http://stackoverflow.com/questions/22996437/release-is-unavailable-not-available-in-automatic-reference-counting-mode

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• Im getting this error 'autorelease' is unavailable: not available in automatic reference counting mode 2 answers
• Custom dealloc and ARC (Objective-C) 1 answer

I'm learning how to program on the iOS operating system using the book "Head first iPhone and iPad development" (second edition).

When I try to compile the code from the book, I get the error that the use release keyword is not allowed in reference counting mode.

Do I have to explicitly release the memory in this case? If yes - how?

ios objective-c

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asked Apr 10 '14 at 18:44 DP_ 1,7441978164

marked as duplicate by Josh Caswell, Caleb, Mick MacCallum Apr 10 '14 at 19:05

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With ARC (introduced with iOS6 or iOS5), let's say it's managed just before the compilation. – Larme Apr 10 '14 at 18:47 

With ARC enabled you don't have to, your book is probably a couple of years old. – pNre Apr 10 '14 at 18:48

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Better get an up to date book, lots of things have changed. – Fructose Apr 10 '14 at 19:25

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Sounds like your book predates ARC. You can develop an application with the same code if you disable ARC in the project settings: But... ARC has been out for a while, and iOS changes fast. If the book doesn't mention ARC, it's a probably sign that it targets a version of the iOS SDK less than 5.0, which is not necessarily the best way to learn iOS development these days. You can roughly translate to an ARC environment by just removing [super dealloc], retain, release, and autorelease from the code you see. But it's valuable to understand why those are there in the first place and why they're no longer necessary with ARC.