archivedDataWithRootObject  存储

BusinessCard *bc = [[BusinessCard alloc] init];  

NSUserDefaults *ud = [NSUserDefaults standardUserDefaults];  

NSData *udObject = [NSKeyedArchiver archivedDataWithRootObject:bc];  

[ud setObject:udObject forKey:@"myBusinessCard"];  

   

udObject = nil;  

udObject = [ud objectForKey:@"myBusinessCard"];  

bc = [NSKeyedUnarchiver unarchiveObjectWithData:udObject] ;