title: C# WPF/XAML Preview Mouse Event for DataGrid
body: <p>I'm using a WPF DataGrid with c#/xaml in Visual Studio 2013.</p>
  
  <p>With SelectionMode="Extended", I'm able to multi-select rows in the grid.</p>
  
  <p>I have a requirement where clicks on one of the columns of the grid are to be ignored relative to row selection.</p>
  
  <p>I setup a PreviewMouseLeftButtonDown event that gets called.
  Since it's a preview event, at the time of the event is processed, the selection in the grid hasn't changed yet.
  I'm able to determine the row and column of the click, so I can determine a click has been made in a column that I don't want</p>
  
  <p>I want to be able to abort the click event at that point so that no change is made to the current selected items in the grid.  Is that possible?</p>
  
  <p>In the mouse down event I tried something like:</p>
  
  <pre><code>    private void GridCtrl_MouseDown(object sender, MouseButtonEventArgs e)
      {
            // ... Other code
            e.Handled = true;
      }
  </code></pre>
  
  <p>But, despite being marked as handled, it still continues and performs the row selection.
  I also have a 'SelectionChanged' event that I see that it later gets into.</p>