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C# MVVM Login Project

I was wondering if somebody can review my code? I am creating a simple login desktop application, just to get used to the MVVM pattern using WPF.

**View**

    <Window x:Class="Login_App.MainWindow"
            xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
            xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
            xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
            xmlns:local="clr-namespace:Login_App"
            xmlns:vm ="clr-namespace:Login_App.ViewModel"
            mc:Ignorable="d"
    
    
        Title="Login" Height="380" Width="650" ResizeMode="NoResize" WindowStartupLocation="CenterScreen">
        <Window.Resources>
            <ResourceDictionary>
                <vm:LoginVM x:Key="vm"/>
            </ResourceDictionary>
        </Window.Resources>
        
        <StackPanel DataContext="{StaticResource vm}">
    
            <TextBlock Text="Username"/>
            <TextBox Text="{Binding Username, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
            <TextBlock Text="Password"/>
            <TextBox Text="{Binding Password, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
            <Button Content="Login"
                    Command="{Binding LoginCommand}"
                    CommandParameter="{Binding User}"/>
    
        </StackPanel>
    </Window>

**LoginView.xaml.cs**

    namespace Login_App
    {
        /// <summary>
        /// Interaction logic for MainWindow.xaml
        /// </summary>
        public partial class MainWindow : Window
        {
            LoginVM viewModel;
            public MainWindow()
            {
                InitializeComponent();
    
                viewModel = Resources["vm"] as LoginVM;
                viewModel.Authenticated += ViewModel_Authenticated;
            }
    
            private void ViewModel_Authenticated(object sender, EventArgs e)
            {
                Close();
            }
        }
    }

**Model**

    namespace Login_App.Model
    {
        public class UserModel
        {
            public int UserID { get; set; }
            public string Username { get; set; }
            public string Email { get; set; }
            public string Password { get; set; }
            public int DepartmentID { get; set; }
            public int GroupID { get; set; }
            public bool Inactive { get; set; }
        }
    }

**ViewModel**

This is the structure:

![Image alt text]
(https://software.codidact.com/uploads/hZBBnKbxeQGABvZGgVWGkcvu)


**LoginVM.cs**

    namespace Login_App.ViewModel
    {
        public class LoginVM : INotifyPropertyChanged
        {
            private UserModel user;
            public UserModel User
            {
                get { return user; }
                set
                {
                    user = value;
                    OnPropertyChanged("User");
                }
            }
    
            private string username;
            public string Username
            {
                get { return username; }
                set
                {
                    username = value;
                    User = new UserModel
                    {
                        Username = username,
                        Password = this.Password
                    };
                    OnPropertyChanged("Username");
                }
            }
    
            private string password;
            public string Password
            {
                get { return password; }
                set
                {
                    password = value;
                    User = new UserModel
                    {
                        Username = this.Username,
                        Password = password
                    };
                    OnPropertyChanged("Password");
                }
            }
    
            public Commands.LoginCommand LoginCommand { get; set; }
    
            public LoginVM()
            {
                LoginCommand = new Commands.LoginCommand(this);
    
                user = new UserModel();
            }
    
            public async void Login()
            {
                bool result = await Helpers.MySQLHelper.Login(User);
                if (result)
                {
                    Authenticated?.Invoke(this, new EventArgs());
                }
            }
    
            public EventHandler Authenticated;
    
            public event PropertyChangedEventHandler PropertyChanged;
            private void OnPropertyChanged(string propertyName)
            {
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }

**Commands > LoginCommand.cs**

    namespace Login_App.ViewModel.Commands
    {
        public class LoginCommand : ICommand
        {
            public LoginVM ViewModel { get; set; }
            public event EventHandler CanExecuteChanged
            {
                add { CommandManager.RequerySuggested += value; }
                remove { CommandManager.RequerySuggested -= value; }
            }
    
            public LoginCommand(LoginVM vm)
            {
                ViewModel = vm;
            }
    
            public bool CanExecute(object parameter)
            {
                UserModel user = parameter as UserModel;
    
                if (user == null)
                    return false;
    
                if (string.IsNullOrEmpty(user.Username))
                    return false;
    
                if (string.IsNullOrEmpty(user.Password))
                    return false;
    
                return true;
    
            }
    
            public void Execute(object parameter)
            {
                ViewModel.Login();
            }
        }
    }

**Helpers > MySQLHelper.cs**

    public class MySQLHelper
    {
        // Login Functionality
        public static async Task<bool> Login(UserModel user)
        {
            try
            {
                /// Query to get count of users from the parameters provided by the user.
                /// On successful Login, the details from the database,
                /// will be saved in the <App.xaml.cs> file.
    
                string mysqlUserDetails = "SELECT COUNT(*), u.id AS UserID, Username, Email, DepartmentID, Inactive" +
                    " FROM users u WHERE Username = @Username AND Password = MD5(@Password)";
    
                using(var connection = new MySqlConnection(ConfigurationManager.ConnectionStrings["MySQL"].ConnectionString))
                {
                    var userDetails = connection.Query<UserModel>(mysqlUserDetails, new { Username = user.Username, Password = user.Password }).ToList();
    
                    // Determine whether to autherize or not
                    if(userDetails.Count == 1)
                    {
                        var details = userDetails.First();
                        App.UserId = details.UserID;
                        App.Username = details.Username;
                        App.Email = details.Email;
                        App.DepartmentID = details.DepartmentID;
                        App.Inative = details.Inactive;

                    }

    
                    
    
                }
                return false;
            }
            catch (Exception ex)
            {
                return false;
            }
        }
    }