protected void gvInvoice_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
int bookingId = DataUtil.GetBookingIdFromGiffiId(double.Parse(lblGiffiRef.Text));
int billingItemId = (int)gvInvoice.DataKeys[e.RowIndex].Value;
BillingRepository repo = new BillingRepository();
repo.DeleteItem(billingItemId, bookingId);
gvInvoice.DataSource = DataUtil.GetBillingItems(bookingId);
gvInvoice.EditIndex = -1;
gvInvoice.DataBind();
}
