ios 委托属性声明中的“弱”和“分配”有什么区别
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What's the difference between 'weak' and 'assign' in delegate property declaration
提问by Firdous
Whats the difference between this:
这有什么区别：
@property (nonatomic, weak) id <SubClassDelegate> delegate;
and this:
和这个：
@property (nonatomic, assign) id <SubClassDelegate> delegate;
I want to use property for delegates.
我想为代表使用财产。
回答by yuji
The only difference between weakand assignis that if the object a weakproperty points to is deallocated, then the value of the weakpointer will be set to nil, so that you never run the risk of accessing garbage. If you use assign, that won't happen, so if the object gets deallocated from under you and you try to access it, you will access garbage.
weak和之间的唯一区别assign是，如果一个weak属性指向的对象被释放，那么weak指针的值将被设置为nil，这样您就永远不会冒访问垃圾的风险。如果你使用assign，那不会发生，所以如果对象从你下面被释放并且你试图访问它，你将访问垃圾。
For Objective-C objects, if you're in an environment where you can use weak, then you should use it.
对于 Objective-C 对象，如果您处于可以使用 的环境中weak，那么您应该使用它。
