title: Object reference not set to an instance of an object when adding DataColumn into DataTable
body: <p>I am getting object reference not set to an instance of an object when I try to add new Column into Datatable. Here is my code:</p>
  
  <pre><code>DataColumn clUniqueID = new DataColumn();
  
  clUniqueID.Caption = "UniqueID";
  clUniqueID.ColumnName = "UniqueID";
  clUniqueID.DataType = typeof(int);
  dtMain.Columns.Add(clUniqueID);
  </code></pre>
  
  <p><code>dtMain</code> is a public DataTable. I put this code on form loading in my Win applicatin and when I try to load my form it is throwing Error.
  Any ideas?</p>