private void fillSupplier(int custId)
    {
        try
        {
            DataTable dtsup = q.GetSupNameId(custId);

            ddlSuplier.DataSource     = dtsup;
            ddlSuplier.DataTextField  = "supplierNameAndID";
            ddlSuplier.DataValueField = "supplier_id";
            ddlSuplier.DataBind();
            ddlSuplier.Items.Insert(0, "--Select--");
        }
        catch (Exception ex)
        {
            g.ShowMessage(this.Page, ex.Message);
        }
    }