title: How to check if any changes were made in DataGridView
body: <p>In my Windows application there is a <code>DataGridView</code> form that shows data from xml file.</p>
  
  <p>Now I want to check if there any changes in <code>DataGridView</code> to ask user does he\she wants to save  current changes that were done in <code>DataGridView</code> to the file.</p>