private void cbo_deploy_period_SelectionChangeCommitted(object sender, EventArgs e)
 {
     if (cbo_deploy_period.Text != string.Empty)
     {
         Guard_deployment.select_deployment_date_by_deploy_id("select_deployment_date_by_deploy_id", Convert.ToInt32(cbo_deploy_period.SelectedValue.ToString()));
     }
 }