其中一些已经被提到过，但以下是我能想到的:

Follow KVO naming rules. Even if you don't use KVO now, in my experience often times it's still beneficial in the future. And if you are using KVO or bindings, you need to know things are going work the way they are supposed to. This covers not just accessor methods and instance variables, but to-many relationships, validation, auto-notifying dependent keys, and so on. Put private methods in a category. Not just the interface, but the implementation as well. It's good to have some distance conceptually between private and non-private methods. I include everything in my .m file. Put background thread methods in a category. Same as above. I've found it's good to keep a clear conceptual barrier when you're thinking about what's on the main thread and what's not. Use #pragma mark [section]. Usually I group by my own methods, each subclass's overrides, and any information or formal protocols. This makes it a lot easier to jump to exactly what I'm looking for. On the same topic, group similar methods (like a table view's delegate methods) together, don't just stick them anywhere. Prefix private methods & ivars with _. I like the way it looks, and I'm less likely to use an ivar when I mean a property by accident. Don't use mutator methods / properties in init & dealloc. I've never had anything bad happen because of it, but I can see the logic if you change the method to do something that depends on the state of your object. Put IBOutlets in properties. I actually just read this one here, but I'm going to start doing it. Regardless of any memory benefits, it seems better stylistically (at least to me). Avoid writing code you don't absolutely need. This really covers a lot of things, like making ivars when a #define will do, or caching an array instead of sorting it each time the data is needed. There's a lot I could say about this, but the bottom line is don't write code until you need it, or the profiler tells you to. It makes things a lot easier to maintain in the long run. Finish what you start. Having a lot of half-finished, buggy code is the fastest way to kill a project dead. If you need a stub method that's fine, just indicate it by putting NSLog( @"stub" ) inside, or however you want to keep track of things.

我知道我在第一次接触Cocoa编程时忽略了这一点。

确保您了解有关NIB文件的内存管理职责。您负责释放所加载的任何NIB文件中的顶级对象。阅读苹果关于这个主题的文档。

尽量避免我现在决定称之为“新类别yaholism”的现象。当Objective-C的新手发现类别时，他们通常会疯狂地为现有的每个类添加有用的小类别(“什么?我可以添加一个方法来转换一个数字到罗马数字到NSNumber岩石上!”)。

不要这样做。

你的代码将更容易移植，更容易理解，因为没有几十个小类别方法散布在20多个基础类之上。

大多数时候，当你真的认为你需要一个类别方法来帮助简化一些代码时，你会发现你永远不会重用这个方法。

还有其他的危险，除非你对你的分类方法进行命名空间(除了疯狂的ddribin，还有谁会这么做呢?)，在你的地址空间中运行的苹果、插件或其他东西也有可能用相同的名称定义相同的分类方法，但副作用略有不同....

好的。现在你已经被警告过了，忽略“不要做这部分”。但是要极度克制。

避免生成

Since you typically(1) don't have direct control over their lifetime, autoreleased objects can persist for a comparatively long time and unnecessarily increase the memory footprint of your application. Whilst on the desktop this may be of little consequence, on more constrained platforms this can be a significant issue. On all platforms, therefore, and especially on more constrained platforms, it is considered best practice to avoid using methods that would lead to autoreleased objects and instead you are encouraged to use the alloc/init pattern.

因此，而不是:

aVariable = [AClass convenienceMethod];

在可能的情况下，你应该使用:

aVariable = [[AClass alloc] init];
// do things with aVariable
[aVariable release];

当您编写自己的方法返回新创建的对象时，您可以利用Cocoa的命名约定，通过在方法名前加上“new”来标记接收方必须释放该对象。

因此，与其:

- (MyClass *)convenienceMethod {
    MyClass *instance = [[[self alloc] init] autorelease];
    // configure instance
    return instance;
}

你可以这样写:

- (MyClass *)newInstance {
    MyClass *instance = [[self alloc] init];
    // configure instance
    return instance;
}

因为方法名以"new"开头，你的API的使用者知道他们负责释放接收到的对象(例如，看NSObjectController的newObject方法)。

你可以通过使用你自己的本地自动释放池来控制。有关这方面的更多信息，请参见自动释放池。

所有这些评论都很棒，但我真的很惊讶没有人提到谷歌的Objective-C风格指南，这是不久前发布的。我认为他们做得很彻底。

IBOutlets

从历史上看，outlet的内存管理一直很差。 当前的最佳实践是将outlet声明为属性:

@interface MyClass :NSObject {
    NSTextField *textField;
}
@property (nonatomic, retain) IBOutlet NSTextField *textField;
@end

使用属性使内存管理语义清晰;如果使用实例变量综合，它还提供了一致的模式。