PIbd-23-Volkov-N.A.-Compute.../ComputersShop/ComputersShopFileImplement/DataFileSingleton.cs

55 lines
2.2 KiB
C#

using ComputersShopFileImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml.Linq;
namespace ComputersShopFileImplement
{
public class DataFileSingleton
{
private static DataFileSingleton? instance;
private readonly string ComponentFileName = "Component.xml";
private readonly string OrderFileName = "Order.xml";
private readonly string ComputerFileName = "Computer.xml";
public List<Component> Components { get; private set; }
public List<Order> Orders { get; private set; }
public List<Computer> Computers { get; private set; }
public static DataFileSingleton GetInstance()
{
if (instance == null)
{
instance = new DataFileSingleton();
}
return instance;
}
public void SaveComponents() => SaveData(Components, ComponentFileName, "Components", x => x.GetXElement);
public void SaveComputers() => SaveData(Computers, ComputerFileName, "Computers", x => x.GetXElement);
public void SaveOrders() => SaveData(Orders, OrderFileName, "Orders", x => x.GetXElement);
private DataFileSingleton()
{
Components = LoadData(ComponentFileName, "Component", x => Component.Create(x)!)!;
Computers = LoadData(ComputerFileName, "Computer", x => Computer.Create(x)!)!;
Orders = LoadData(OrderFileName, "Order", x => Order.Create(x)!)!;
}
private static List<T>? LoadData<T>(string filename, string xmlNodeName, Func<XElement, T> selectFunction)
{
if (File.Exists(filename))
{
return
XDocument.Load(filename)?.Root?.Elements(xmlNodeName)?.Select(selectFunction)?.ToList();
}
return new List<T>();
}
private static void SaveData<T>(List<T> data, string filename, string xmlNodeName, Func<T, XElement> selectFunction)
{
if (data != null)
{
new XDocument(new XElement(xmlNodeName, data.Select(selectFunction).ToArray())).Save(filename);
}
}
}
}