Swift 核心数据更改 bool 存储

Posted 2023-02-24

【中文标题】Swift 核心数据更改 bool 存储

【英文标题】：Swift core data change bool stored

【发布时间】：2020-06-19 16:02:26

【问题描述】：

我正在为列表制作和扩展一个应用程序，并在执行过程中添加额外的数据。我添加了一个布尔值来将项目标记为已完成。

我想更改存储在核心数据中的布尔值。我可以添加和删除订单，但现在我正在寻找更改属性。请问我可以帮助我改变这些的最佳方式吗？

我已完成功能更改，但不知道如何让它在我的核心数据管理器中工作。

class CoreDataManager 

static let shared = CoreDataManager(moc: NSManagedObjectContext.current)

var moc: NSManagedObjectContext

private init(moc: NSManagedObjectContext) 
    self.moc = moc


private func fetchOrder(name: String) -> Order? 

    var orders = [Order]()

    let request: NSFetchRequest<Order> = Order.fetchRequest()
    request.predicate = NSPredicate(format: "name == %@", name)

    do 
        orders = try self.moc.fetch(request)
     catch let error as NSError 
        print(error)
    

    return orders.first



func changeCompleated(name:String, completed: Bool) 
      do 
        if let order = fetchOrder(name: name) 
            self.moc.perform 

            
                 try self.moc.save()
             
          catch let error as NSError 
             print(error)
         


func deleteOrder(name: String) 

    do 
        if let order = fetchOrder(name: name) 
            self.moc.delete(order)
            try self.moc.save()
        
     catch let error as NSError 
        print(error)
    



func getAllOrders() -> [Order] 

    var orders = [Order]()

    let orderRequest: NSFetchRequest<Order> = Order.fetchRequest()

    do 
        orders = try self.moc.fetch(orderRequest)
     catch let error as NSError 
        print(error)
    

    return orders



func saveOrder(id: UUID, name: String, type: String, qty: Double, urgent: Bool, complete: Bool) 

    let order = Order(context: self.moc)
    order.id = id
    order.name = name
    order.type = type
    order.qty = qty
    order.urgent = urgent
    order.complete = complete

    do 
        try self.moc.save()
     catch let error as NSError 
        print(error)
       

【参考方案1】：

差不多，只要加一行改变值，perform块就不需要了

func changeCompleated(name: String, completed: Bool) 

    guard let order = fetchOrder(name: name) else  return 
    do 
       order.complete = completed
       try self.moc.save()
     catch 
       print(error)
    

你也可以缩短fetchOrder

private func fetchOrder(name: String) -> Order? 

    let request: NSFetchRequest<Order> = Order.fetchRequest()
    request.predicate = NSPredicate(format: "name == %@", name)

    do 
        return try self.moc.fetch(request).first
     catch 
        print(error)