Diplom_O/DataBase/CorrStajDB.cs

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Diplom_O.DataBase
{
  public class CorrStaj
  {
    [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }
		[ForeignKey("Chel")]
		public int ChelId { get; set; }
		public Chel Chel { get; set; }
		[ForeignKey("TypeStaj")]
		public int TypeStajId { get; set; }
		public TypeStaj TypeStaj { get; set; }
		public int Year { get; set; }
		public int Month { get; set; }
		public int Day { get; set; }
		public bool AddFlag { get; set; }
	}

	public static partial class FuncDB
	{
		public static void CorrStajValid(CorrStaj obj)
		{
			try
			{
				if (obj == null)
					throw new Exception("Ошибка инициализации стажа.");
			}
			catch
			{
				throw;
			}
		}

		public static CorrStaj CorrStajGetById(int id)
		{
			try
			{
				using (var db = new MainDB())
				{
					var corrstaj =
						from a in db.CorrStajy
						where a.Id == id
						select a;
					try
					{
						return corrstaj.Single();
					}
					catch
					{
						return null;
					}
				}
			}
			catch
			{
				throw;
			}
		}
		public static CorrStaj CorrStaj(int chelId, string name)
		{
			try
			{
				using (var db = new MainDB())
				{
					var ts = TypeStajGetByName(name);
					if (ts == null)
						return null;
					var corrstaj =
						from a in db.CorrStajy
						where a.TypeStajId == ts.Id && a.ChelId == chelId
						select a;
					try
					{
						return corrstaj.Single();
					}
					catch
					{
						return null;
					}
				}
			}
			catch
			{
				throw;
			}
		}

		public static void CorrStajAdd(CorrStaj obj)
		{
			try
			{
				CorrStajValid(obj);
				using (var db = new MainDB())
				{
					db.CorrStajy.Add(obj);
					db.SaveChanges();
				}
			}
			catch
			{
				throw;
			}
		}
		public static void CorrStajChange(CorrStaj obj)
		{
			try
			{
				CorrStajValid(obj);
				var localObjById = CorrStajGetById(obj.Id);
				var localObjByName = CorrStaj(obj.ChelId, TypeStajGetById(obj.TypeStajId).Name);
				if (localObjById == null)
					throw new Exception("Корректировка стажа не существует.");
				if (localObjByName != null &&
					localObjByName.Id != localObjById.Id)
					throw new Exception("Корректировка стажа существует.");
				using (var db = new MainDB())
				{
					db.CorrStajy.Update(obj);
					db.SaveChanges();
				}
			}
			catch
			{
				throw;
			}
		}
		public static void CorrStajDelete(CorrStaj obj)
		{
			try
			{
				if (obj == null)
					return;
				var localObj = CorrStajGetById(obj.Id);
				if (localObj == null)
					throw new Exception("Корректироваки стажа не существует.");
				using (var db = new MainDB())
				{
					db.CorrStajy.Remove(localObj);
					db.SaveChanges();
				}
			}
			catch
			{
				throw;
			}
		}

		public static CorrStaj[] CorrStajList(int chelId)
		{
			try
			{
				using (var db = new MainDB())
				{
					var res = (
						from a in db.CorrStajy
						where a.ChelId == chelId
						select a
						).ToList();
					return res.ToArray();
				}
			}
			catch
			{
				throw;
			}
		}

	}


}