+ (id)self {    return (id)self;}- (id)self {    return self;}+ (Class)class {    return self;}- (Class)class {    return object_getClass(self);}+ (Class)superclass {    return self->superclass;}- (Class)superclass {    return [self class]->superclass;}+ (BOOL)isMemberOfClass:(Class)cls {    return object_getClass((id)self) == cls;}- (BOOL)isMemberOfClass:(Class)cls {    return [self class] == cls;}+ (BOOL)isKindOfClass:(Class)cls {    for (Class tcls = object_getClass((id)self); tcls; tcls = tcls->superclass) {        if (tcls == cls) return YES;    }    return NO;}- (BOOL)isKindOfClass:(Class)cls {    for (Class tcls = [self class]; tcls; tcls = tcls->superclass) {        if (tcls == cls) return YES;    }    return NO;}+ (BOOL)isSubclassOfClass:(Class)cls {    for (Class tcls = self; tcls; tcls = tcls->superclass) {        if (tcls == cls) return YES;    }    return NO;}复制代码

问如下打印啥？

NSLog(@"[self class]%@",[self class]);       NSLog(@"[super class]%@",[super class]);       NSLog(@"==================");       NSLog(@"[self superClass]%@",[self superclass]);       NSLog(@"[super superClass]%@",[super superclass]);复制代码

NSLog(@"%d",[[NSObject class] isKindOfClass:[NSObject class]]);        NSLog(@"%d",[[NSObject class] isMemberOfClass:[NSObject class]]);        NSLog(@"%d",[[Person class] isKindOfClass:[Person class]]);        NSLog(@"%d",[[Person class] isMemberOfClass:[Person class]]);复制代码