Validation By Annotation in Wpf using MVVM

View

 <Window x:Class="WpfPrismTutorial.Views.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:WpfPrismTutorial"
        mc:Ignorable="d"
        prism:ViewModelLocator.AutoWireViewModel="True"
        xmlns:prism="http://prismlibrary.com/"
        xmlns:valid="clr-namespace:WpfPrismTutorial.Validations"
        Title="MainWindow" Height="450" Width="800">
    <Window.Resources>
        <ControlTemplate x:Key="errorTemplate">
            <StackPanel Orientation="Horizontal">
            <AdornedElementPlaceholder x:Name="ErrorHolder" >
                <Border BorderBrush="red" BorderThickness="1" />
            </AdornedElementPlaceholder>
            <TextBlock  Text="{Binding [0].ErrorContent}" VerticalAlignment="Center" HorizontalAlignment="Right" Foreground="Red"/>
        </StackPanel>

        </ControlTemplate>
    </Window.Resources>
    <Grid VerticalAlignment="Center" HorizontalAlignment="Left">
     
        <StackPanel Orientation="Horizontal" Grid.Row="1">
            <TextBlock Text="Validation by Annotation" Margin="5,5"/>
            <TextBox Text="{Binding MainWindowModel.ValidationByAnnotation,UpdateSourceTrigger=PropertyChanged,
                       ValidatesOnExceptions=True}" Validation.ErrorTemplate="{StaticResource errorTemplate}"  Height="30" Width="300"/>
        </StackPanel>
   
    </Grid>
</Window>

ViewModel 

public class MainWindowViewModel : BindableBase
    {
        private MainWindowModel mainWindowModel = new MainWindowModel();

        public MainWindowModel MainWindowModel
        {
            get { return mainWindowModel; }
            set { SetProperty(ref mainWindowModel, value); }
        }
  }

Model

 public class MainWindowModel : BindableBase
    {
          #region Validation By Annotation

        private string _validationByAnnotation;
        [Required(ErrorMessage = "Validation By Annotation should not empty")]
        public string ValidationByAnnotation
        {
            get { return _validationByAnnotation; }

            set
            {
                Validate(value, "ValidationByAnnotation");
                SetProperty(ref _validationByAnnotation, value);
            }
        }
        private void Validate<T>(T value, string propertyName)
        {
            Validator.ValidateProperty(value, new ValidationContext(this, null, null)
            {
                MemberName = propertyName
            });
        }
        #endregion

    }