private List <CustomerInventoryGroup> AddSelectedCustomers()
        {
            List <CustomerInventoryGroup> selectedCustomers = CUSTOMERS;

            foreach (GridViewRow row_customer in gvCustomers.Rows)
            {
                CheckBox ck          = ((CheckBox)row_customer.FindControl("chkItems"));
                Image    imgCustomer = (Image)row_customer.FindControl("imgCustomer");
                if (ck.Checked)
                {
                    CustomerReferenceLink CRL     = CustInvGroupManager.GetCustomerLinkByCustCode(imgCustomer.ToolTip);
                    BranchClass           branch  = BranchManager.GetBranchByCode(CRL.BranchCode);
                    AccountClass          account = AccountManager.GetAccountByCode(branch.AccountCode);
                    string BrandName;
                    if (string.IsNullOrEmpty(HttpUtility.HtmlDecode(row_customer.Cells[3].Text)) ||
                        string.IsNullOrWhiteSpace(HttpUtility.HtmlDecode(row_customer.Cells[3].Text)))
                    {
                        BrandName = brandManager.GetBrandByCode(CRL.BrandCode).BrandDescription;
                    }
                    else
                    {
                        BrandName = row_customer.Cells[3].Text;
                    }

                    CustomerInventoryGroup customer = new CustomerInventoryGroup
                    {
                        CustomerNumber = int.Parse(imgCustomer.AlternateText),
                        CustomerName   = row_customer.Cells[2].Text,
                        BrandName      = BrandName,
                        AccountName    = account.AccountName,
                        BranchName     = branch.BranchName
                    };
                    if (!IsAlreadySelected(CUSTOMERS, customer.CustomerNumber))
                    {
                        if (string.IsNullOrEmpty(customer.AccountName) || string.IsNullOrWhiteSpace(customer.AccountName))
                        {
                            hfWarningHandler_ModalPopupExtender.Show();
                        }
                        else
                        {
                            selectedCustomers.Add(customer);
                        }
                    }
                }
            }
            return(selectedCustomers);
        }