如何保存数组到CoreData？ [英] How to save Array to CoreData?

问题描述

我需要将数组保存到Core Data。

  let array = [8，17.7，18，21，0 ，0，34] 
  

数组中的值和值的数量是可变的。

1。我在NSManagedObject类中声明了什么？

  class PBOStatistics：NSManagedObject，Equatable {
 @NSManaged var date：NSDate 
 @NSManaged var average：NSNumber 
 @NSManaged var historicalAverage：NSNumber 
 @NSManaged var total：NSNumber 
 @NSManaged var historicalTotal：NSNumber 
 @NSManaged var ordersCount：NSNumber 
 @NSManaged var historicalOrdersCount：NSNumber 
 @NSManaged var values：[Double] // is it ok？ 
 
 @NS管理的变量位置：PBOLocation 
 
} 
  

2。我在.xcdatamodel中声明了什么？

3。如何将其保存在我的实体中？（我使用MagicalRecord）

  let statistics =（PBOStatistics.MR_createInContext context）as！PBOStatistics）
 statistics.values = [8，17.7，18，21，0，0，34] //够了吗？ 
  

解决方案

好，我做了一些研究和测试。使用可变性类型，解决方案很简单：

1。我在NSManagedObject类中声明了什么？

  @NSManaged var values：[NSNumber]也可以使用
  

2。我在.xcdatamodel中声明了什么？

可变形数据类型。 b
$ b

3。如何将其保存在我的实体中？

  statistics！.values = [23，45，567.8，123 ，0，0] //只是这个
  

NSArray或NSDictionary作为可变属性。这将使用NSCoding将数组或字典序列化为NSData属性（并在访问时适当地反序列化） - 源

或者如果要声明为二进制数据，然后阅读此简单文章：

I need to save my array to Core Data.

let array = [8, 17.7, 18, 21, 0, 0, 34]

The values inside that array, and the number of values are variable.

1. What do I declare inside my NSManagedObject class?

class PBOStatistics: NSManagedObject, Equatable {
    @NSManaged var date: NSDate
    @NSManaged var average: NSNumber
    @NSManaged var historicAverage: NSNumber
    @NSManaged var total: NSNumber
    @NSManaged var historicTotal: NSNumber
    @NSManaged var ordersCount: NSNumber
    @NSManaged var historicOrdersCount: NSNumber
    @NSManaged var values: [Double]  //is it ok?

    @NSManaged var location: PBOLocation

}

2. What do I declare inside my .xcdatamodel?

3. How do I save this in my Entity? (I use MagicalRecord)

let statistics = (PBOStatistics.MR_createInContext(context) as! PBOStatistics)
statistics.values = [8, 17.7, 18, 21, 0, 0, 34] //is it enough?

解决方案

Ok, I made some research and testing. Using Transformable type, solution is simple:

1. What do I declare inside my NSManagedObject class?

@NSManaged var values: [NSNumber]  //[Double] also works

2. What do I declare inside my .xcdatamodel?

Transformable data type.

3. How do I save this in my Entity?

statistics!.values = [23, 45, 567.8, 123, 0, 0] //just this

"You can store an NSArray or an NSDictionary as a transformable attribute. This will use the NSCoding to serialize the array or dictionary to an NSData attribute (and appropriately deserialize it upon access)" - Source

Or If you want to declare it as Binary Data then read this simple article:

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