protected void fBillProvinceID_SelectedIndexChanged(object sender, EventArgs e)
    {
        DADistrict daDistrictBilling = new DADistrict();

        fBillDistrictID.DataSource = daDistrictBilling.USP_District_GetDataForComboBox_ByProvinceID(int.Parse(fBillProvinceID.SelectedValue));
        fBillDistrictID.DataBind();
    }
    override protected Boolean GetDataComboBox()
    {
        try
        {
            DAOrderStatus daOrderStatus = new DAOrderStatus();
            fOrderStatusID.DataSource = daOrderStatus.USP_OrderStatus_GetDataForComboBox();
            fOrderStatusID.DataBind();

            DAPayment daPayment = new DAPayment();
            fPaymentID.DataSource = daPayment.USP_Payment_GetDataForComboBox();
            fPaymentID.DataBind();

            DAShipping daShipping = new DAShipping();
            fShippingID.DataSource = daShipping.USP_Shipping_GetDataForComboBox();
            fShippingID.DataBind();

            DAProvince daProvinceBilling = new DAProvince();
            fBillProvinceID.DataSource = daProvinceBilling.USP_Province_GetDataForComboBox();
            fBillProvinceID.DataBind();

            DADistrict daDistrictBilling = new DADistrict();
            fBillDistrictID.DataSource = daDistrictBilling.USP_District_GetDataForComboBox_ByProvinceID(int.Parse(fBillProvinceID.SelectedValue));
            fBillDistrictID.DataBind();


            DAProvince daProvinceShipping = new DAProvince();
            fShipProvinceID.DataSource = daProvinceShipping.USP_Province_GetDataForComboBox();
            fShipProvinceID.DataBind();


            DADistrict daDistrictShipping = new DADistrict();
            fShipDistrictID.DataSource = daDistrictShipping.USP_District_GetDataForComboBox_ByProvinceID(int.Parse(fShipProvinceID.SelectedValue));
            fShipDistrictID.DataBind();

            DACustomer daCustomer = new DACustomer();
            fCustomerID.DataSource = daCustomer.USP_Customer_GetDataForComboBox();
            fCustomerID.DataBind();

            DAProvince daProvince = new DAProvince();
            fProvinceID.DataSource = daProvince.USP_Province_GetDataForComboBox();
            fProvinceID.DataBind();

            DACustomerGroup daCustomerGroup = new DACustomerGroup();
            fCustomerGroupID.DataSource = daCustomerGroup.USP_CustomerGroup_GetDataForComboBox();
            fCustomerGroupID.DataBind();


            //LoadCategory();
            return(true);
        }
        catch (Exception ex)
        {
            ShowErrorMes("Lỗi hệ thống: " + ex.Message);
            return(false);
        }
    }