如何使用Swift以正确的值保存CoreData中的解码值

guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {
    return
}
let managedContext = appDelegate.persistentContainer.viewContext

guard let entity = NSEntityDescription.entity(forEntityName: "EntityName", in: managedContext) else {
    return
}
let object = NSManagedObject(entity: entity, insertInto: managedContext)
object.setValue(value, forKey: "propertyName")

do {
    try managedContext.save()
} catch let error as NSError {
    print("Could not save. \(error), \(error.userInfo)")
}

let fetchRequest = NSFetchRequest<NSManagedObject>(entityName: "EntityName")

do {
    let fetchedResults = try managedContext.fetch(fetchRequest)
    for data in fetchedResults {
        if let value = data.value(forKey: "propertyName") {
            // 处理检索到的数据
        }
    }
} catch let error as NSError {
    print("Could not fetch. \(error), \(error.userInfo)")
}