Programm_Wirl/AA-Klassen/Kosten.cs

using BrightIdeasSoftware;
using Npgsql;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DatenDB
{
	public enum KostenKat
	{
		FixLohn = 0,
		Variabel = 1,
		FixMiete = 2,
		Rest = 3
	}
	public class Kosten
	{
		private const string COLUMNS = "kosten_id, konto_nr, bezeichnung, datum, kategorie, betrag";
		private const string SUMCOLUMNS = "min(kosten_id), konto_nr, min(bezeichnung) as bezeichnung, min(datum) as datum, min(kategorie) as kategorie, sum(betrag) as betrag";
		private const string TABLE = "kundenverwaltung.kosten";
		public Kosten()
		{
		}
		public static List<Kosten> GetList(int? aktjahr, int? monat, int? aktquartal, bool aktiv, int vpjahr, int[] quartale)
		{
			DatenbankConnection.GetConnection().Open();
			List<Kosten> resultList = new List<Kosten>();
			using (NpgsqlCommand command = new NpgsqlCommand())
			{
				command.Connection = DatenbankConnection.GetConnection();
				if (monat == null || monat == 0)
				{
					if (aktquartal == null || aktquartal == 0)
					{
						if (quartale == null || quartale.Length == 0)
						{
							command.CommandText = $"select {SUMCOLUMNS} from {TABLE} where date_part('year', datum) = {aktjahr} group by konto_nr order by konto_nr, datum";
						}
						else
						{
							command.CommandText = $"select {SUMCOLUMNS} from {TABLE} where date_part('year', datum) = {aktjahr} and date_part('quarter', datum) between {quartale.Min()} and {quartale.Max()} group by konto_nr order by konto_nr, datum";
						}
					}
					else
					{
						if (aktquartal == 4) command.CommandText = $"select {SUMCOLUMNS} from {TABLE} where date_part('year', datum) = {aktjahr} group by konto_nr order by konto_nr, datum";
						else command.CommandText = $"select {SUMCOLUMNS} from {TABLE} where date_part('quarter', datum) = {aktquartal} and date_part('year', datum) = {aktjahr} group by konto_nr order by konto_nr, datum";
					}

				}
				else command.CommandText = $"select {SUMCOLUMNS} from {TABLE} where date_part('month', datum) = {monat} and date_part('year', datum) = {aktjahr} group by konto_nr, datum order by konto_nr, datum";
				NpgsqlDataReader reader = command.ExecuteReader();
				while (reader.Read()) resultList.Add(new Kosten(reader));
				reader.Close();
			}

			DatenbankConnection.GetConnection().Close();
			return resultList;
		}
    public static List<Kosten> GetUpdateList(string kontonr)
    {
      DatenbankConnection.GetConnection().Open();
      List<Kosten> resultList = new List<Kosten>();
      using (NpgsqlCommand command = new NpgsqlCommand())
      {
        command.Connection = DatenbankConnection.GetConnection();
				if(kontonr != null) command.CommandText = $"select {COLUMNS} from {TABLE} where konto_nr = {kontonr}";
        NpgsqlDataReader reader = command.ExecuteReader();
        while (reader.Read()) resultList.Add(new Kosten(reader));
        reader.Close();
      }

      DatenbankConnection.GetConnection().Close();
      return resultList;
    }
		public static double GetSummeKategorie()
		{
			DatenbankConnection.GetConnection().Open();
			double kosten = 0;
			using (NpgsqlCommand command = new NpgsqlCommand())
			{
				command.Connection = DatenbankConnection.GetConnection();


				NpgsqlDataReader reader = command.ExecuteReader();
				while (reader.Read()) kosten = reader.IsDBNull(0) ? 0 : reader.GetDouble(0);
				reader.Close();
			}

			DatenbankConnection.GetConnection().Close();

			return kosten;
		}
		public static Kosten GetKosten(int? kostenid, string bez)
		{
			DatenbankConnection.GetConnection().Open();
			Kosten kosten = new Kosten();
			using (NpgsqlCommand command = new NpgsqlCommand())
			{
				command.Connection = DatenbankConnection.GetConnection();

				if (!string.IsNullOrEmpty(bez)) command.CommandText = $"select {COLUMNS} from {TABLE} where LOWER(bezeichnung)  = '{bez}'";

				NpgsqlDataReader reader = command.ExecuteReader();
        while (reader.Read()) kosten = new Kosten(reader);
				reader.Close();
			}

			DatenbankConnection.GetConnection().Close();
			return kosten;
		}
		public Kosten(NpgsqlDataReader reader)
		{
			this.KostenID = reader.GetInt32(0);
			this.KontoNr = reader.GetInt32(1);
			this.Bezeichnung = reader.IsDBNull(2) ? string.Empty : reader.GetString(2);
			this.Datum = reader.GetDateTime(3);
			this.Kategorie = (KostenKat)reader.GetInt16(4);
			this.Betrag = reader.IsDBNull(5) ? null : (double?)reader.GetDouble(5);
		}
		public int GetKostenID(int kontonr, DateTime datum)
		{
			DatenbankConnection.GetConnection().Open();
			using (NpgsqlCommand command = new NpgsqlCommand())
			{
				command.Connection = DatenbankConnection.GetConnection();
				command.CommandText = $"select kosten_id from {TABLE} where konto_nr = '{kontonr}' and datum = '{datum}'";

				int result = 0;
				NpgsqlDataReader reader = command.ExecuteReader();
				while (reader.Read()) result = reader.GetInt16(0);
				reader.Close();
				DatenbankConnection.GetConnection().Close();

				return result;
			}
		}
    public static int GetKontoNr(string bez)
    {
      DatenbankConnection.GetConnection().Open();
      using (NpgsqlCommand command = new NpgsqlCommand())
      {
        command.Connection = DatenbankConnection.GetConnection();
        command.CommandText = $"select konto_nr from {TABLE} where bezeichnung = {bez}";

        int result = 0;
        NpgsqlDataReader reader = command.ExecuteReader();
        while (reader.Read()) result = reader.GetInt16(0);
        reader.Close();
        DatenbankConnection.GetConnection().Close();

        return result;
      }
    }
    public int Save()
		{
			DatenbankConnection.GetConnection().Open();

			using (NpgsqlCommand command = new NpgsqlCommand())
			{
				command.Connection = DatenbankConnection.GetConnection();

				if (this.KostenID.HasValue & this.KostenID != 0)
				{
					command.CommandText = $"update {TABLE} set konto_nr = :p1, bezeichnung = :p2, datum = :p3, kategorie = :p4, betrag = :p5 WHERE kosten_id = :p0";
				}
				else
				{
					command.CommandText = "select nextval('kundenverwaltung.kosten_seq')";
					this.KostenID = (int)(long)command.ExecuteScalar();
					command.CommandText = $"insert into {TABLE} ({COLUMNS}) values (:p0, :p1, :p2, :p3, :p4, :p5)";
				}

				command.Parameters.AddWithValue("p0", this.KostenID);
				command.Parameters.AddWithValue("p1", this.KontoNr);
				command.Parameters.AddWithValue("p2", string.IsNullOrEmpty(this.Bezeichnung) ? (object)DBNull.Value : this.Bezeichnung);
				command.Parameters.AddWithValue("p3", this.Datum);
				command.Parameters.AddWithValue("p4", (int)this.Kategorie);
				command.Parameters.AddWithValue("p5", this.Betrag.HasValue ? (object)this.Betrag.Value : (object)DBNull.Value);

				int result = command.ExecuteNonQuery();
				DatenbankConnection.GetConnection().Close();
				return result;
			}
		}

		[OLVIgnore]
		public int? KostenID { get; set; } = null;

		[OLVColumn(DisplayIndex = 0, TextAlign = System.Windows.Forms.HorizontalAlignment.Right, IsEditable = false)]
		public int KontoNr { get; set; }

		[OLVColumn(DisplayIndex = 1, IsEditable = false)]
		public string Bezeichnung { get; set; }

		[OLVColumn(DisplayIndex = 2, TextAlign = System.Windows.Forms.HorizontalAlignment.Center, AspectToStringFormat = "{0:d}", IsEditable = false)]
		public DateTime Datum { get; set; }

		[OLVColumn(DisplayIndex = 3, TextAlign = System.Windows.Forms.HorizontalAlignment.Center, IsEditable = true)]
		public KostenKat Kategorie { get; set; }

		[OLVColumn(DisplayIndex = 4, TextAlign = System.Windows.Forms.HorizontalAlignment.Right, AspectToStringFormat = "{0:c}", IsEditable = true)]
		public double? Betrag { get; set; } = null;
	}
}