Coredata和NSManagedObject生成的子类与关系 [英] Coredata and Generated subclass for NSManagedObject with relations

问题描述

使用选项创建NSManagedObject子类为2个实体生成子类Xcode创建了4个文件...好，我不明白如何使用创建的函数来管理关系

Generating subclasses for 2 Entities with the option "Create NSManagedObject SubClass" Xcode creates 4 files ... well, i can't understand how to use functions created to manage relations

@interface Person (CoreDataGeneratedAccessors)

- (void)addPersonContactObject:(Contacts *)value;
- (void)removePersonContactObject:(Contacts *)value;
- (void)addPersonContact:(NSSet *)values;
- (void)removePersonContact:(NSSet *)values;

@end

这只是接口，我要实现这些方法？和什么时候可以使用？
我发现一对多关系是用NSSet管理的...不是一个可变对象是我的怀疑与什么有关的吗？

This is interface only, have i to implement these methods? and when they can be useful ? I found that one to many relations are managed with NSSet... not a mutable object is my doubt something related with that ?

推荐答案

您不必实现它们，它们被声明为阻止编译器警告此处。

You don't have to implement them, they are declared there to prevent compiler warnings as described here.

您可以使用* Object来从关系中添加和删除单个项目，但是通常更容易从一个（即，从联系人设置人，而不是从另一个方向）。

You'd use the *Object ones to add and remove individual items from the relationship, but it is usually simpler to manage that from the "one" side of the one-to-many relationship (that is, to set the person from the contact, not the other way round).

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