private void OnSubmitCompleted(SubmitOperation so)
 {
     if (so.HasError)
     {
         MessageBox.Show(string.Format("Submit Failed: {0}", so.Error.Message));
         so.MarkErrorAsHandled();
     }
     else
     {
         QLThuebaoDomainContext dstb = new QLThuebaoDomainContext();
         InvokeOperation<System.Nullable<int>> p = dstb.Excute_p_doiaccint(txtusr.Text.Trim(), txtusrn.Text.Trim());
         p.Completed += new EventHandler(Completed);
     }
 }