title: how I can show the sum of in a datagridview column?
body: <p>I need to show the sum of the <code>count</code> column from this <code>datagridview</code>, but I don't know how I can get to the data in the datagridview.</p>
  
  <p>When I click on the button, I want to show <code>94</code> in <code>label1</code>.</p>
  
  <p>How can this be done?</p>
  
  <p><img src="https://i.stack.imgur.com/Nzoeu.jpg" alt="alt text"></p>