using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml.Serialization;

namespace ConsoleApplication2
{
    public static class DataBaseManager
    {
        public static void MakeDataSet(string fname, string sheetName, DataSet dset,
            string info = "Pomyślnie utworzono DataSet...")
        {
            try
            {
                var myConnection = new System.Data.OleDb.OleDbConnection(
                    "Provider=Microsoft.ACE.OLEDB.12.0;" +
                    "Data Source=" + fname + ";" +
                    "Extended Properties=\"Excel 12.0;" +
                    "HDR=YES;\"");
                var myCommand = new System.Data.OleDb.OleDbDataAdapter("select * from [" + sheetName + "$]",
                    myConnection);
                myCommand.Fill(dset);
                myConnection.Close();
                Console.WriteLine(info);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
        }

        //serializacja listy do pliku XML
        public static void ToXml(string filename, Type t, Object obj)
        {
            var xs = new XmlSerializer(t);
            using (var sw = new StreamWriter(filename))
            {
                xs.Serialize(sw, obj);
            }
            Console.WriteLine("Zapisano plik na dysku");
        }

        //deserializacja pliku XML do listy podanej w 2 parametrze
        public static Object FromXml(string filename, Type t)
        {
            try
            {
                using (var sr = new StreamReader(filename))
                {
                    var xs = new XmlSerializer(t);
                    return xs.Deserialize(sr);
                }
            }
            catch (Exception)
            {
                Console.WriteLine("Błąd odczytu pliku XML");
                return null;
            }
        }
    }
}

/*
Użycie metod
	....

	ToXml("Nazwa_pliku.xml",typeof(List<Zadanie>), nazwa_serializowanego_obiektu);

	Zadania zadania;
	zadania = (Zadania)FromXml("Nazwa_pliku.xml", typeof(List<Zadanie>));
*/