先給出官方介紹
-
isKindOfClass:Returns a Boolean value that indicates whether the receiver is an instance of given class or an instance of any class that inherits from that class.
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isMemberOfClass:Returns a Boolean value that indicates whether the receiver is an instance of a given class.
共同點:
isKindOfClass與isMemberOfClass都是NSObject中比較Class的方法。
不同點:
1.isKindOfClass用來判斷某個對象是否屬於某個類,或者是屬於某個派生類。
2.isMemberOfClass用來判斷某個對象是否為當前類的實例。
PS:isMemberOfClass不能檢測任何的類都是基於NSObject類這一事實,而isKindOfClass可以。
下面就用一個小栗子講解一下兩者的區別:
1、首先創建個People類基於NSObject,然后創建個Student類基於People類
- (void)viewDidLoad { [super viewDidLoad]; People *people = [[People alloc] init]; Student *student = [[Student alloc] init]; if ([people isKindOfClass:[People class]]) { NSLog(@"people iskinofclass People"); } if ([people isKindOfClass:[NSObject class]]) { NSLog(@"people iskinofclass NSObject"); } if ([student isMemberOfClass:[Student class]]) { NSLog(@"student ismemberOfClass People"); } if (![student isMemberOfClass:[NSObject class]]) { NSLog(@"student isbelog NSObject"); } }
2、查看打印結果:四個log全部打印,驗證了上邊對兩者的論述。
上述概念理解后作者給大家出個思考題如下:
BOOL rez1 = [(id)[NSObject class] isKindOfClass:[NSObject class]]; BOOL rez2 = [(id)[NSObject class] isMemberOfClass:[NSObject class]]; BOOL rez3 = [(id)[Student class] isKindOfClass:[People class]]; BOOL rez4 = [(id)[Student class] isMemberOfClass:[Student class]];
看看大家對這兩者含義究竟了解了多少(如果一下子就答出來了,證明真的是懂了。)
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最后給出輸出結果:rez1為真、其他均為假。