title: How can I add a new column and data to a datatable that already contains data?
body: <p>How do I add a new <code>DataColumn</code> to a <code>DataTable</code> object that already contains data?</p>
  
  <p>PseudoCode</p>
  
  <pre><code>//call SQL helper class to get initial data 
  DataTable dt = sql.ExecuteDataTable("sp_MyProc");
  
  dt.Columns.Add("NewColumn", type(System.Int32));
  
  foreach(DataRow row in dr.Rows)
  {
      //need to set value to NewColumn column
  }
  </code></pre>