WPF uses and expected results of AccessText class
<p>I was going through the class <code>AccessText</code> today. I couldn't identify exact use  and results of using this class.</p>

<blockquote>
  <p>If you use <code>AccessText</code> with a Label and use <code>Target</code> property as a
  <code>TextBox</code>, the <code>TextBox</code> will get focus when <code>access key</code> is pressed.see below code:</p>
</blockquote>

<pre><code>&lt;StackPanel&gt;
    &lt;Label Target="{Binding ElementName=txtbox}"&gt;
        &lt;AccessText&gt;_first_second&lt;/AccessText&gt;
    &lt;/Label&gt;
    &lt;TextBox Name="txtbox" Width="100" Height="50"/&gt;
&lt;/StackPanel&gt;
</code></pre>

<blockquote>
  <p>If you use <code>AccessText</code> with a <code>Label</code> and use Target property as a
  <code>Buton</code> , the <code>Button</code> <code>Click</code> event will get executed when <code>access
  key</code> is pressed.</p>
</blockquote>

<p>So my questions are </p>

<blockquote>
  <p><strong><em>1.what is the definitive behavior of <code>AccessText</code> Class? If I have to predict it's uses with other type of controls like <code>DataGrid</code>, <code>ComboBox</code>,
  <code>RadioButton</code>? how can i be sure of expected result?</em></strong></p>
  
  <p><strong><em>2.Why is this class derived from <code>FrameworkElement</code>? What applications does it have as a <code>FrameworkElement</code>? seems a bit more for
  just specifying Accesskeys etc.</em></strong></p>
</blockquote>