PIbd21_Makarov_DV_FlowerShop/FlowerShop/FlowerShopFileImplement/DataFileSingleton.cs

50 lines
2.0 KiB
C#

using FlowerShopFileImplement.Models;
using System.Xml.Linq;
namespace FlowerShopFileImplement
{
internal class DataFileSingleton
{
private static DataFileSingleton? instance;
private readonly string ComponentFileName = "Component.xml";
private readonly string OrderFileName = "Order.xml";
private readonly string FlowerFileName = "Flower.xml";
public List<Component> Components { get; private set; }
public List<Order> Orders { get; private set; }
public List<Flower> Flowers { 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 SaveFlowers() => SaveData(Flowers, FlowerFileName, "Flowers", x => x.GetXElement);
public void SaveOrders() => SaveData(Orders, OrderFileName, "Orders", x => x.GetXElement);
private DataFileSingleton()
{
Components = LoadData(ComponentFileName, "Component", x => Component.Create(x)!)!;
Flowers = LoadData(FlowerFileName, "Flower", x => Flower.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);
}
}
}
}