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    <p>What you have done will work. You can <code>retain</code> and <code>release</code> objects from any scope you choose, so long as it all evens out (and the object is deallocated when it is no longer needed by any other object).</p> <p>But what you are doing is not conventional. If you want to allow the object to live on past the life of a method (so that you can <code>return</code> it and have it picked up by the method caller) then you should use <code>autorelease</code>.</p> <p>In your example, the first method should probably not retain ownership of the string. It should release it and let the caller pick it up. But, of course, if you <code>release</code> it in the method it will be instantly deallocated. So instead you can <code>autorelease</code> it. By autoreleasing it, your first method is saying <em>"I no longer need this object and relinquish my ownership, but please keep it in memory a little while longer so my caller can retain it if it needs to"</em>.</p> <p>Here's an example:</p> <pre><code>- (NSString *)createString { /* Create a string. This method owns it. */ NSString *str = [[NSString alloc] init]; /* Autorelease it. This method does not own it, but wants it to stay in memory temporarily. */ [str autorelease] /* Return it. It will stay in memory till the end of the current run loop */ return str; } - (void)viewDidLoad{ NSString *name = [self createString]; /* We now have a copy of the string. Nobody owns it. */ /* It is due to be released at the end of the current run loop. */ /* If we want to take ownership of it and prevent deallocation, we should retain it. */ [name retain]; } </code></pre> <p>This behaviour is used all throughout the Cocoa APIs. When you see class methods that return a new object, that object will be autoreleased. For example, when you call <code>[NSArray arrayWithObjects:@"One", @"Two", @"Three", nil]</code> you are asking the NSArray class to create an array for you. If exists outside of the <code>arrayWithObjects:</code> method thanks to its autoreleased status. If you do not <code>retain</code> it, it will be released at the end of the current run loop.</p>
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    1. POCan I return allocated object and release it outside function?
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    1. USSimon Cave
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    1. POCan I return allocated object and release it outside function?
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    1. COHis first method name begins with "alloc" - by convention, it's supposed to return an object that the caller owns.
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      1. USSherm Pendley
    2. COThank you for your answer! I understand how it works now!
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      1. USpnmn
    3. COThen, why we do not retain new array instance after this: NSArray *a = [NSArray arrayWithObjects:@"111", @"222", nil]; ? (like this: [a retain];)
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      1. USAlmas Adilbek
 

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