protected void btnProcessApprove_Click(object sender, EventArgs e)
 {
     try
     {
         PurchaseOrderService.ApprovedPurchaseOrder(txtDocumentNo.Text,
                                                    EmployeeService.GetEmployee(UserSessionHelper.GetCurrentUserName()).ID, txtApproveReason.Text);
         LoadData();
         WebFormHelper.SetLabelTextWithCssClass(lblStatusAddEdit, String.Format("Purchase Order {0} has been marked as APPROVED", txtDocumentNo.Text), LabelStyleNames.AlternateMessage);
     }
     catch (Exception ex)
     {
         WebFormHelper.SetLabelTextWithCssClass(lblStatusAddEdit, ex.Message, LabelStyleNames.ErrorMessage);
     }
 }