iOS KVC valueForKeyPath学习心得

#import <Foundation/Foundation.h>

@interface myClass1 : NSObject
@property (nonatomic, copy) NSString *str;

@end

@implementation myClass1

@end

@interface myClass : NSObject
{
}
@property (nonatomic, retain) myClass1 *item;

@end

@implementation myClass

- (id)init{
if(self = [super init]){
[self setValue:[[myClass1 alloc]init] forKey:@"item"];//如果不给item设置值，则最后得到的item.str为空！
}
return self;
}
@end

int main(int argc, const char * argv[]) {
@autoreleasepool {
[class1 setValue:@"this is item.str" forKeyPath:@"item.str"];
NSLog(@"item.str = %@",[class1 valueForKeyPath:@"item.str"]);
}
return 0;
}

高级用法：http://www.thinksaas.cn/group/topic/347021/