Question

我正在获取AddressBook的内容，而后者又被复制到一个数组中。现在我想将这个数组保存到CoreData中。我知道如何在CoreData中插入单个值。我是如何遍历数组来做同样的事情？

这是我试过的。

 -(void)fetchAddressBook
 {
    ABAddressBookRef UsersAddressBook = ABAddressBookCreateWithOptions(NULL, NULL);

   //contains details for all the contacts
   CFArrayRef ContactInfoArray = ABAddressBookCopyArrayOfAllPeople(UsersAddressBook);

   //get the total number of count of the users contact
   CFIndex numberofPeople = CFArrayGetCount(ContactInfoArray);

   //iterate through each record and add the value in the array
    for (int i =0; i<numberofPeople; i++) {
    ABRecordRef ref = CFArrayGetValueAtIndex(ContactInfoArray, i);
    ABMultiValueRef names = (__bridge ABMultiValueRef)((__bridge NSString*)ABRecordCopyValue(ref, kABPersonCompositeNameFormatFirstNameFirst));
       NSLog(@"name from address book = %@",names); // works fine
       NSString *contactName = (__bridge NSString *)(names);
      [self.reterivedNamesMutableArray addObject:contactName];
       NSLog(@"array content = %@", [self.reterivedNamesMutableArray lastObject]); //This shows null.


}
}

-(void)saveToDatabase
{
  AddressBookAppDelegate *appDelegate =[[UIApplication sharedApplication]delegate];
  NSManagedObjectContext *context = [appDelegate managedObjectContext];
  NSManagedObject *newContact;

  for (NSString *object in self.reterivedNamesMutableArray) // this array holds the name of contacts which i want to insert into CoreData. 
  { 
     newContact = [NSEntityDescription insertNewObjectForEntityForName:@"AddressBook"   inManagedObjectContext:context];
     [newContact setValue:@"GroupOne" forKey:@"groups"];
     [newContact setValue:object forKey:@"firstName"];
      NSLog(@"Saved the contents of Array"); // this doesn't log.
  }
  [context save:nil];
  }

Answer 1

_{（未来读者请注意：此答案指的是问题的第一个版本。
为了解决这个问题，问题中的代码已经多次更新。）}

您的代码只创建一个对象newContact，并且循环会修改同一个对象一次又一次。如果你想要多个对象（每个地址一个），你必须分别创建每个对象：

for (NSString *object in self.reterivedNamesMutableArray) 
{
    newContact = [NSEntityDescription insertNewObjectForEntityForName:@"AddressBook"   inManagedObjectContext:context];
    [newContact setValue:@"GroupOne" forKey:@"groups"];
    [newContact setValue:object forKey:@"firstName"];
}
[context save:nil];

如何在iOS 6中保存Core Data中的Array内容

1 个答案: