---

<Window x:Class="finyk.Pages.LoginWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Авторизация"
        Height="415"
        Width="752"
        WindowStartupLocation="CenterScreen"
        ResizeMode="NoResize">

    <Grid Margin="20">
        <StackPanel VerticalAlignment="Center">
            <TextBlock Text="Авторизация"
                       FontSize="24"
                       FontWeight="Bold"
                       HorizontalAlignment="Center"
                       Margin="0,0,0,20"/>

            <TextBlock Text="Логин"/>
            <TextBox x:Name="LoginTb"
                     Height="30"
                     Margin="0,5,0,10"/>

            <TextBlock Text="Пароль"/>
            <PasswordBox x:Name="PasswordTb"
                         Height="30"
                         Margin="0,5,0,20"/>

            <Button Content="Войти"
                    Height="35"
                    Click="LoginBtn_Click"/>
        </StackPanel>
    </Grid>
</Window









public partial class LoginWindow : Window
    {
        public LoginWindow()
        {
            InitializeComponent();
            ConnectToDb.conDb = new demkaEntities();
        }

        private void LoginBtn_Click(object sender, RoutedEventArgs e)
        {
            string login = LoginTb.Text.Trim();
            string password = PasswordTb.Password.Trim();

            if (string.IsNullOrWhiteSpace(login) || string.IsNullOrWhiteSpace(password))
            {
                MessageBox.Show("Введите логин и пароль");
                return;
            }

            var currentUser = ConnectToDb.conDb.Users.FirstOrDefault(x =>
                x.Login == login && x.Password == password);

            if (currentUser != null)
            {
                MessageBox.Show("Успешный вход");

                MainWindow mainWindow = new MainWindow();
                mainWindow.Show();
                this.Close();
            }
            else
            {
                MessageBox.Show("Неверный логин или пароль");
            }
        }
    }