Swift - Delete CoreData row

Question

我尝试从核心数据中删除一行。我处理该行，但没有删除。当我尝试context.delete(( 时，它需要在 (( 中要求NSManagedObject。如何将此结果转换为 NSManagedObject？

func deleteElement(postUid:String){
let appDel:AppDelegate = (UIApplication.shared.delegate as! AppDelegate)
let context:NSManagedObjectContext = appDel.persistentContainer.viewContext
let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "Posts")
let predicate = NSPredicate(format: "postUid == %@", postUid as CVarArg)
fetchRequest.predicate = predicate
do {
let result = try context.fetch(fetchRequest)
print("Result (result)")

try context.save()
} catch {
print("Error (error)")
}
}

结果打印

Result [<Posts: 0x6080002901d0> (entity: Posts; id: 0xd000000000640000 <x-coredata://9A330E28/Posts/p25> ; data: {
item = "<relationship fault: 0x60c00022b900 'item'>";
lastMessageTime = "2018-05-23";
parentUid = nil;
postUid = "15e43d16";
title = Title;
userUid = ".."; })]

Answer 1

let result = try context.fetch(request)
for object in result {
let obj = object as! NSManagedObject
context.delete(obj)
}
try context.save()

您基本上需要获取对象，然后逐个删除它们。然后，您只需像往常一样保存上下文即可。