KVO 的kvc 和点 触发

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#import "ViewController.h"

@interface ViewController ()

@property (nonatomic,copy)NSString *name;

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    //KVO

    [self addObserver:self forKeyPath:@"name" options:NSKeyValueObservingOptionNew|NSKeyValueObservingOptionOld context:nil];

    //kvc

    [selfsetValue:@"张雨涵"forKey:@"name"];

    //点语法

    self.name = @"zhangcc";

    // Do any additional setup after loading the view, typically from a nib.

}

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

    NSLog(@"keyName = %@",keyPath);

    NSLog(@"change = %@",change);

}

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*编译结果

2019-02-21 14:04:41.742268+0800 面试题[9125:958213] keyName = name

2019-02-21 14:04:41.742626+0800 面试题[9125:958213] change = {

    kind = 1;

    new = "\U5f20\U96e8\U6db5";

    old = "";

}

2019-02-21 14:04:41.742820+0800 面试题[9125:958213] keyName = name

2019-02-21 14:04:41.742998+0800 面试题[9125:958213] change = {

    kind = 1;

    new = zhangcc;

    old = "\U5f20\U96e8\U6db5";

}

（'''）