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  • xcode KVC:Key Value Coding 键值编码

    赋值

    // 能修改私有成员变量

    - (void)setValue:(id)value forKey:(NSString *)key;

    - (void)setValue:(id)value forKeyPath:(NSString *)keyPath;

    - (void)setValuesForKeysWithDictionary:(NSDictionary *)keyedValues;

    取值

    // 能取得私有成员变量的值

    - (id)valueForKey:(NSString *)key;

    - (id)valueForKeyPath:(NSString *)keyPath;

    - (NSDictionary *)dictionaryWithValuesForKeys:(NSArray *)keys;

    KVO:Key Value Observing 键值监听

    使用步骤:

        1>.添加监听器

        // 利用b对象来监听a对象name属性的改变

        [a addObserver:b forKeyPath:@"name" options:NSKeyValueObservingOptionOld | NSKeyValueObservingOptionNew context:@"test"];

        2>.在监听器中实现监听方法

        -(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change     context:(void *)context

        {

            NSLog(@"%@ %@ %@ %@", object, keyPath, change, context);

        }

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  • 原文地址:https://www.cnblogs.com/fleas/p/5565363.html
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