swift - saveWithBlock 方法中的 MagicalRecord 未找到具有 MR_FindFirstByAttribute 的现有实体 - Swift

Question

我正在尝试使用此 block 导入实体

 MagicalRecord.saveWithBlock({   (moc: NSManagedObjectContext!) in                

      //parsing inquiries
      for (index: String, jsonInquiry: JSON) in json["data"]["inquiries"] {

           var idInquiry =  jsonInquiry["id_inquiry"].int! 
           var inquiry: Inquiry

           //trying to find existing entity
           if let existingInquiry = Inquiry.MR_findFirstByAttribute("id", withValue: idInquiry, inContext: moc) as? Inquiry {
                inquiry = existingInquiry
                println("fetching existing inquiry: \(idInquiry)")
            } else {
                inquiry = Inquiry.MR_createInContext(moc) as! Inquiry
                println("creating new inquiry: \(idInquiry)")
            }
            ...
       }
  }    

Only first entity is found as existing, others are created as new

但是当我使用以下命令一次性预取所有实体时:

 MagicalRecord.saveWithBlock({  (moc: NSManagedObjectContext!) in

      //preFetch all entities        
      var existingInquiries = [Int:Inquiry]()
      for item in Inquiry.MR_findAllInContext(moc) {
           if let existingItem = item as? Inquiry {
                existingInquiries[ existingItem.id ] = existingItem
           }
      }

      //parsing inquiries
      for (index: String, jsonInquiry: JSON) in json["data"]["inquiries"] {
           ....     
           var idInquiry =  jsonInquiry["id_inquiry"].int! 
           var inquiry: Inquiry

           if let existingInquiry = existingInquiries[idInquiry] {
                inquiry = existingInquiry
                    println("fetching existing inquiry: \(idInquiry)")
                } else {
                    inquiry = Inquiry.MR_createInContext(moc) as! Inquiry
                    println("fetching new inquiry: \(idInquiry)")
                }
          }
          ....
   }

all entities are found as existing

有人可以发现我的错误或错误吗？也许我缺少一些基本的东西。我为此苦苦挣扎了几个小时

谢谢

我使用 XCODE 版本 6.3 (6D570) 和 Swift 1.2

Answer 1

我发现我的错误了a 在我的循环中包含此代码 - 它应该是上一级:)

for inquiry in existingInquiries.values {
       if !contains(importedInquiries, inquiry) {
                inquiry.MR_deleteInContext(moc)
       }
}