Objective-C 类别：我可以为不属于我的类别的方法添加属性吗？
我想使用类别来使原始类上的方法也可用作属性。
A 类：
@interface ClassA
- (NSString*)foo;
@end
A 类类别
@interface ClassA (Properties)
- (void)someCategoryMethod;
@property (nonatomic, readonly) NSString *foo;
@end
现在，当我这样做时，它似乎可以工作（编辑：也许它不起作用，它不会抱怨，但我看到了奇怪的情况），但它给了我警告因为我没有在我的类别实现中综合该属性。我如何告诉编译器一切实际上都很好，因为原始类为我合成了属性？
I want to use a category to make a method on the original class available as a property as well.
Class A:
@interface ClassA
- (NSString*)foo;
@end
Class A category
@interface ClassA (Properties)
- (void)someCategoryMethod;
@property (nonatomic, readonly) NSString *foo;
@end
Now when I do this, it seems to work (EDIT: Maybe it doesn't work, it doesn't complain but I am seeing strangeness), but it gives me warnings because I am not synthesizing the property in my category implementation. How do I tell the compiler everything is actually just fine since the original class synthesizes the property for me?
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这是您收到的警告：
警告：属性'foo'需要定义方法'-foo' - 使用@synthesize，@dynamic或提供方法实现要抑制此警告，请将其包含在您的实现：
@dynamic foo;Here's the warning you're getting:
warning: property ‘foo’ requires method '-foo' to be defined - use @synthesize, @dynamic or provide a method implementationTo suppress this warning, have this in your implementation:
@dynamic foo;如果在类别的接口中声明了某些内容，则其定义属于您的类别的实现。
If something's declared in your category's interface, its definition belongs in your category's implementation.
我就此写了两篇文章，尽管这个概念与您提出的问题略有不同。
这比方法调配要好得多，至少：更安全。
I wrote two articles on this, though the concept is slightly different from the question you're asking.
This is a LOT better than method swizzling, at least: way safer.