title: TypeCoverter and ContentProperty in same class
body: <p>I am trying to implement my custom control, of <code>UIElement</code> type.
  I would like to implement type converter of one of the control properties, which is the direct content of the control (like in <code>ContentControl</code>).</p>
  
  <p>I know, that for support the direct content I have to use <code>ContentPropertyAttribute</code>, I also have a <code>TypeConverter</code> and my own type for the direct content property.</p>
  
  <p>So - it looks like this:</p>
  
  <p>XAML:</p>
  
  <pre><code>&lt;controls:MyControl&gt;    
  &lt;![CDATA[
  Typical string to convert.
  ]]&gt;
  &lt;controls:MyControl&gt;
  </code></pre>
  
  <p>MyControl:</p>
  
  <pre><code>[ContentProperty("MyProperty")]
  [TypeConverter(typeof(MyTypeConverter))]
  public class MyControl : UIElement
  {
      public MyType MyProperty
      {
          get { return (MyType)GetValue(MyPropertyProperty); }
          set { SetValue(MyPropertyProperty, value); }
      }
  
      public static readonly DependencyProperty MyPropertyProperty =
          DependencyProperty.Register("MyProperty", typeof(MyType), typeof(MyControl), new PropertyMetadata(null));
  }
  </code></pre>
  
  <p>I hope implementation of <code>MyTypeConverter</code> and <code>MyType</code> are not important here.</p>
  
  <p>The problem is that, when I am trying to compile the code, I have an error:</p>
  
  <pre><code>error MC3090: TypeConverter syntax error encountered while processing initialization string '
  error MC3090:     Typical string to convert.
  error MC3090:     '.  Element attributes are not allowed on objects created via TypeConverter. Line 52 Position 8.
  </code></pre>
  
  <p>Obviously, my project is not working.
  Is there any chance to implement it that way? Or maybe I have to change my approach?
  Thank you in advance for any help!</p>