慕桂英546537
运行一个简单的测试,我以为我要记录什么有效,什么无效。我经常看到人们在检查该对象的类是否是另一个类的成员或等于另一个类。对于下面的行,我们有一些格式不正确的数据,可以是NSArray,NSDictionary或(null)。NSArray *hits = [[[myXML objectForKey: @"Answer"] objectForKey: @"hits"] objectForKey: @"Hit"];这些是执行的测试:NSLog(@"%@", [hits class]);if ([hits isMemberOfClass:[NSMutableArray class]]) { NSLog(@"%@", [hits class]);}if ([hits isMemberOfClass:[NSMutableDictionary class]]) { NSLog(@"%@", [hits class]);}if ([hits isMemberOfClass:[NSArray class]]) { NSLog(@"%@", [hits class]);}if ([hits isMemberOfClass:[NSDictionary class]]) { NSLog(@"%@", [hits class]);}if ([hits isKindOfClass:[NSMutableDictionary class]]) { NSLog(@"%@", [hits class]);}if ([hits isKindOfClass:[NSDictionary class]]) { NSLog(@"%@", [hits class]);}if ([hits isKindOfClass:[NSArray class]]) { NSLog(@"%@", [hits class]);}if ([hits isKindOfClass:[NSMutableArray class]]) { NSLog(@"%@", [hits class]);}isKindOfClass工作得很好,而isMemberOfClass没有。