title: Adding new column to datagridview
body: <p>I'd like to add new column to existing datagridview so:</p>
  
  <pre><code>DataColumn col = new DataColumn(( dataGridView1.ColumnCount+1).ToString());
  dataGridView1.Columns.Add(col);
  </code></pre>
  
  <p>But it doesn't work.. how to do it?</p>