public void PopulateData(int invoiceID)
{
rsInvoiceHead = SalesOrder.GetInvoiceHead(invoiceID);
rsInvoiceDetail = SalesOrder.GetInvoiceDetail(invoiceID);
lblConfirmation.Visible = false;
btnConfirmInvoice.Visible = false;
btnGeneratePDF.Visible = true;
PopulateData();
}