title: How do I capture "Click" events on a DataGrid column headers
body: <p>It appears that the <code>DataGrid</code> that comes with .NET 4 does not contain an event for both column and row header clicks. I want to receive events for the column header click as I want to provide my own sorting behaviour and turn off the default sorting, this is because my view-model is a paginated model that will only display 25/50/100 rows at a time, the default sorting will of-course sort the current page only.</p>
  
  <p>Now I could create a new <code>DataGridColumnHeader</code> style which contains a clickable element and  and set <code>ColumnHeaderStyle</code>, though this just seems like a pain as I'll have trouble figuring out things like which column it was that got clicked etc.</p>
  
  <p>Anyone else come up against this and solved it?</p>