title: How To Select multiple cells in DataGridView
body: <p>I have a DataGridView in my Form. The Functionality is as below.</p>
  
  <ul>
  <li>Clicking on header selects the whole column.</li>
  <li>Clicking on any cell other than the column header selects the entire row</li>
  </ul>
  
  <p>I have set multiselect to true. I am able to select multiple cells by using the mouse. but I want to do it programmatically.</p>