int类型的setter/getter的正确属性是什么?-Whatisthecorrectattributeforasetter/getterforanint?

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Here is a great post about the difference between atomic and nonatomic:

这里有一篇关于原子和非原子的区别的文章:

Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic changes the generated code. If you are writing your own setter/getters, atomic/nonatomic/retain/assign/copy are merely advisory.

假设您是@ synzing方法实现，原子vs非原子更改生成的代码。如果您正在编写自己的setter/getter，那么原子/非原子/保留/分配/复制仅仅是咨询。

With atomic, the synthesized setter/getter will ensure that a whole value is always returned from the getter or set by the setter, regardless of setter activity on any other thread. That is, if thread A is in the middle of the getter while thread B calls the setter, an actual viable value -- an autoreleased object, most likely -- will be returned to the caller in A.

对于原子，合成的setter/getter将确保所有值始终从getter中返回或由setter设置，而不考虑任何其他线程上的setter活动。也就是说，如果线程A位于getter的中间，而线程B调用setter，那么一个实际可行的值——最可能是一个autoreleated对象——将在A中返回给调用者。

In nonatomic, no such guarantees are made. Thus, nonatomic is considerably faster than atomic.

在非原子中，没有这样的保证。因此，非原子比原子快得多。

What atomic does not do is make any guarantees about thread safety. If thread A is calling the getter simultaneously with thread B and C calling the setter with different values, thread A may get any one of the three values returned -- the one prior to any setters being called or either of the values passed into the setters in B and C. Likewise, the object may end up with the value from B or C, no way to tell.

原子不做的是保证线程安全。如果线程与线程同时调用getter B和C调用setter与不同价值观,线程A可能会返回的三个值中的任何一个,前一个被调用setter或者值传递到setter的B和C .同样,价值的对象可能会从B或C,无法告诉。

Ensuring data integrity -- one of the primary challenges of multi-threaded programming -- is achieved by other means.

确保数据完整性(多线程编程的主要挑战之一)是通过其他方式实现的。

Note that the default is atomic, so the last example is equivalent to

注意，默认值是原子的，所以最后一个示例等价于

@property (atomic) int myInt

Another default value is assign, therefore these two options are equivalent:

另一个默认值是assign，因此这两个选项是等价的:

@property (nonatomic, assign) int myInt
@property (nonatomic) int myInt

And, similarly, the following are also equivalent

同样，下面的内容也是等价的

@property (atomic, assign) int myInt
@property (atomic) int myInt

EDIT: As Josh points out, atomic being included is a hypothetical example.

编辑:正如Josh所指出的，原子被包含是一个假设的例子。

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defaults are assign and atomic

默认值是赋值和原子的

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It's more of a style issue than an issue of technical correctness. For an int type, the only thing that has to true the assign modifier (because you don't retain scalars). Otherwise, it's context specific: readwrite or readonly, atomic or nonatomic, it depends on the application.

与其说是技术正确性问题，不如说是风格问题。对于int类型，唯一需要对赋值修饰符进行赋值的东西(因为不保留标量)。否则，它是特定于上下文的:readwrite或readonly、atomic或nonatomic，这取决于应用程序。

Note that if you don't specify a modifier, the default applies (atomic, readwrite, assign). So your example your first other example are identical, and the third only differs in atomicity.

注意，如果没有指定修饰符，则默认应用(原子、读写、赋值)。你的例子你的第一个例子是相同的，第三个只是原子性不同。

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@property(nonatomic,assign)int myVariable;

@ property(原子,分配)int myVariable;

always remember assign will be used for primitive data types like int , bool

永远记住，assign将用于像int、bool这样的原始数据类型