Automatically validating business entities in WPF using custom binding and attributes

<Application x:Class="POC.Validatie.App"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    StartupUri="MainWindow.xaml">
    <Application.Resources>
        <ControlTemplate x:Key="validationTemplate">
                <StackPanel Orientation="Horizontal">
                    <Border BorderBrush="Green" BorderThickness="1">
                        <AdornedElementPlaceholder  x:Name="adorner" />
                    </Border>
                    <TextBlock Foreground="Red" FontSize="10pt" 
                               Text="{Binding ElementName=adorner, Path=AdornedElement.(Validation.Errors).CurrentItem.ErrorContent}" />
                </StackPanel>
        </ControlTemplate>
    </Application.Resources>
</Application>