protected void btnUpdate_Click(object sender, EventArgs e)
 {
     try
     {
         objAdmin.SNO                = Convert.ToInt32(ViewState["SNO"]);
         objAdmin.TotalCylinders     = Convert.ToInt32(txtTotalCylinders1.Text);
         objAdmin.AvailableCylinders = Convert.ToInt32(txtAvailableCylinders1.Text);
         string s = objAdmin.UpdateCylinders();
         lblMsg1.Text = s;
         btnShow_Click(sender, e);
     }
     catch (Exception ex)
     {
     }
 }