AvaloniaProjectApp/AvaloniaApplication2/ViewModels/MainWindowViewModel.cs

using AvaloniaApplication2.Models;
using Avalonia.Controls;
using System.Collections.ObjectModel;
using System.Linq;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using AvaloniaPractic;
using AvaloniaPractic.Models;

namespace AvaloniaApplication2.ViewModels
{
    public partial class MainWindowViewModel: ViewModelBase
    {
        Pavlov41pContext _db = new Pavlov41pContext();

        [ObservableProperty] string login;
        [ObservableProperty] string password;
        [ObservableProperty] string info;
        [ObservableProperty] Logined? currentUser;
        [ObservableProperty] UserControl page = new Autorization();

        public static MainWindowViewModel Self;
        public MainWindowViewModel()
        {
            Self = this;
        }
        
        //Метод для авторизации
        public void Enter()
        {
            currentUser = _db.Logineds
                .Include(x => x.Role)
                .FirstOrDefault(x => x.Login == login && x.Password == password);

            if (currentUser != null)
            {
                Info = "Добро пожаловать!";
                Password = "";

                //Переход на страницу в зависимости от роли
                switch (currentUser.Role.Name)
                {
                    case "admin":
                        Page = new AdminWindow();
                        break;
                    case "user":
                        Page = new UserWindow();
                        break;
                }
            } else
            {
                Info = "Неверный логин или пароль";
                Password = "";
            }
        }

        public void Save() =>_db.SaveChanges();
        public void GoBack() => Page = new Autorization();
    }
}