核心数据模型对象保存的最佳实践

Question

我有两个实体“人”和“汽车”来自网络服务。 我需要通过核心数据将其存储在sqlite中。我想知道将save方法与NSmanagedobject绑定或在实用程序或管理器中以不同方式编写时最好的方法是什么？

**Approach 1** 

@interface Person : NSManagedObject

@property (nonatomic, retain) NSString * title;

- (void) saveManagedObject:(NSDictionary*)response //Responsible for init the person object and save in context

@end

**Approach 2**

@interface CoreDataUtility : NSObject

- (void) saveManagedObject:(NSDictionary*)response //Responsible for create the person object and save in context

@end

Answer 1

Short answer: both methods are good, especially if you do not want to deal with 3rd party frameworks. Those might be useful, but the also bear some risks; this would be another question.

It is perfectly fine to have a creation method in the `NSManagedObject´ subclass (in a category or elsewhere*).

However, you should make it a class method, not an instance method.

To create an entity in a DataManager class is also a feasible and a very common pattern. The good thing about the utility class is that you can more easily maintain multiple contexts for background operations.

*) I do not use categories any more because it is rare to change the model by more than a few fields- I prefer to edit them manually.