title: Capture mouse clicks on WPF TextBox
body: <p>I want to capture mouse clicks on a <code>TextBox</code>:</p>
  
  <pre><code>&lt;Window x:Class="WpfApplication2.Window1"
          xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
          xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
          Title="Window1" Height="300" Width="300"&gt;
      &lt;Grid&gt;
          &lt;TextBox x:Name="t" MouseDown="TextBox_MouseDown"
                   MouseLeftButtonDown="TextBox_MouseLeftButtonDown"
                   MouseLeftButtonUp="TextBox_MouseLeftButtonUp"
                   Height="50" /&gt;
      &lt;/Grid&gt;
  &lt;/Window&gt;
  </code></pre>
  
  <p>Now I only receive a mouse click event when the user first enters the <code>TextBox</code>. After this <code>TextBox</code> has keyboard focus, I do not receive mouse click event anymore. Any idea how to get this working?</p>