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  • instancesRespondToSelector与respondsToSelector的区别

    Test1.h

    @interface Test1 : NSObject
    
    - (void)objectFun;
    
    + (void)classFun;
    
    @end

    Test1.m

    @implementation Test1
    
    - (void)objectFun
    {
        NSLog(@"object function");
    }
    
    + (void)classFun
    {
        NSLog(@"class function");
    }
    
    @end

    测试类:

    BOOL flag;
    
    flag = [Test1 instancesRespondToSelector:@selector(objectFun)]; //YES
    
    flag = [Test1 instancesRespondToSelector:@selector(classFun)]; //NO
    
    flag = [Test1 respondsToSelector:@selector(objectFun)]; //NO
    
    flag = [Test1 respondsToSelector:@selector(classFun)]; //YES
    
    Test1 *obj = [[Test1 alloc] init];
    
    flag = [obj respondsToSelector:@selector(objectFun)]; //YES
    
    flag = [obj respondsToSelector:@selector(classFun)]; //NO

    总结:

    1. instancesRespondToSelector只能写在类名后面,respondsToSelector可以写在类名和实例名后面。

    2. [类 instancesRespondToSelector]判断的是该类的实例是否包含某方法,等效于:[该类的实例 respondsToSelector]。

    3. [类 respondsToSelector]用于判断是否包含某个类方法。

     

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  • 原文地址:https://www.cnblogs.com/CoderWayne/p/3872776.html
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