问题描述
我正在一个iPhone项目，我想从一个NSMutableArray检索一个对象，从数组中删除对象，然后使用它。代码看起来像这样：
I'm working on an iPhone project where I would like to retrieve an object from an NSMutableArray, remove the object from the array and then use it later. The code looks something like this:
NSMutableArray * array;
// fill the array
NSObject * obj = [array lastObject];
[array removeLastObject];
// do something with obj (in the same function)
在被访问的对象上有一个retain。这是安全吗？我想假设这只会工作，如果lastObject自动释放对象，这是一个我不能弄清楚如果它。
array is the only entity with a retain on the object that is being accessed. Is this safe to do? I would assume that this would only work if lastObject autoreleased the object which is something that I can't figure out if it does.
推荐答案
为什么不调用
[array removeLastObject]
在函数的结尾？这是少一个释放/保留。
at the end of your function? That's one fewer release/retain. It might make your code more readable/less cluttered.
对于记录，：
id anObject = [[anArray objectAtIndex:0] retain];
[anArray removeObjectAtIndex:0];
[anObject someMessage];
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