protected void btnAddBilling_Click(object sender, EventArgs e)
        {
            //Insert Values into discounts table using linq
            TreasureLandDataClassesDataContext db = new TreasureLandDataClassesDataContext();
            BillingCategory addBilling = new BillingCategory();
            addBilling.BillingCategoryDescription = txtDesciption.Text;
            addBilling.BillingCategoryTaxable = cbTaxable.Checked;

            db.BillingCategories.InsertOnSubmit(addBilling);
            db.SubmitChanges();
            gvBilling.DataBind();
        }
 partial void UpdateBillingCategory(BillingCategory instance);
 partial void DeleteBillingCategory(BillingCategory instance);
 partial void InsertBillingCategory(BillingCategory instance);