title: WPF Validation & IDataErrorInfo
body: <p>A note - the classes I have are <code>EntityObject</code> classes!</p>
  
  <p>I have the following class:</p>
  
  <pre><code>public class Foo
  {
      public Bar Bar { get; set; }
  }
  
  public class Bar : IDataErrorInfo
  {
      public string Name { get; set; }
  
      #region IDataErrorInfo Members
      string IDataErrorInfo.Error
      {
          get { return null; }
      }
  
      string IDataErrorInfo.this[string columnName]
      {
          get
          {
              if (columnName == "Name")
              {
                  return "Hello error!";
              }
              Console.WriteLine("Validate: " + columnName);
              return null;
          }
      }
      #endregion
  }
  </code></pre>
  
  <p>XAML goes as follows:</p>
  
  <pre><code>&lt;StackPanel Orientation="Horizontal" DataContext="{Binding Foo.Bar}"&gt;
       &lt;TextBox Text="{Binding Path=Name, ValidatesOnDataErrors=true}"/&gt;
  &lt;/StackPanel&gt;
  </code></pre>
  
  <p>I put a breakpoint and a <code>Console.Writeline</code> on the validation there - I get no breaks. The validation is not executed. Can anybody just press me against the place where my error lies?</p>