wpf validation

Hej..

Jeg vil lige have hjælp til noget validation...

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Data;
 using System.Windows.Documents;
 using System.Windows.Input;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Navigation;
 using System.Windows.Shapes;
 
 namespace Datavalidation
 {
     /// <summary>
     /// Interaction logic for MainWindow.xaml
     /// </summary>
     public partial class MainWindow : Window
     {
         private string name;
 
         public string Name
         {
             get { return name; }
             set {
                 if (String.IsNullOrEmpty(value))
                 {
                     throw new ApplicationException("Customer name is mandatory.");
                 }
                 name = value; }
         }
 
 
 
         public MainWindow()
         {
             
             InitializeComponent();
         }
         
         
     }
 }

<Window x:Class="Datavalidation.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
       
    <Grid>

        

        <TextBox Margin="72,101,220,182">
            <TextBox.Text>
                <Binding Path="Name">
                    <Binding.ValidationRules>
                        <ExceptionValidationRule/>
                    </Binding.ValidationRules>
                </Binding>
            </TextBox.Text>
        </TextBox>
    </Grid>
</Window>

Jeg kan ikke får det her til at virke...?? Tekstbox må ikke være tom..