AvaloniaKnuScool/ViewModels/AuthorizationViewModel.cs

using System;
using System.Collections.Generic;
using System.Linq;
using AvaloniaApplication1.Models;
using MsBox.Avalonia.Enums;
using MsBox.Avalonia;
using Npgsql.EntityFrameworkCore.PostgreSQL.Infrastructure.Internal;
using ReactiveUI;

namespace AvaloniaApplication1.ViewModels
{
	public class AuthorizationViewModel : ReactiveObject
	{
        public static ScoolContext DB = new ScoolContext();

		private string _login;
        private string _pass;

        public string Login
		{
            get => _login; set => this.RaiseAndSetIfChanged(ref _login, value);
        }

        public string Pass
        {
            get => _pass; set => this.RaiseAndSetIfChanged(ref _pass, value);
        }

        public int Auth()
        {
            if(Login != null && Pass!=null) 
            {
                User user = DB.Users.Where(x=>x.Login == Login && x.Password == Pass).FirstOrDefault();
                if(user != null)
                {
                    return user.IdUser;
                }
                else
                {
                    var box = MessageBoxManager.GetMessageBoxStandard("Ïðåäóïðåæäåíèå", "Âàñ íåò");
                    box.ShowAsync();
                    return 0;
                }
            }
            else
            {
                var box = MessageBoxManager.GetMessageBoxStandard("Ïðåäóïðåæäåíèå", "Ïîëÿ íå çàïîëíåíû");
                box.ShowAsync();
                return 0;
            }
        }
    }
}