private void SetDataSources()
        {
            var allProducts    = ProductOperations.GetAll()?.ItemList ?? new List <ProductDto>();
            var branchProducts = ddlBranches.SelectedValue == "0" ? new List <ProductDto>() : ProductOperations.GetAllByStoreId(int.Parse(ddlBranches.SelectedValue));

            RadListBoxSource.DataSource = branchProducts.Count > 0 ? allProducts.Where(p => !branchProducts.Contains(p)) : allProducts;
            RadListBoxSource.DataBind();
            RadListBoxDestination.DataSource = branchProducts;
            RadListBoxDestination.DataBind();
        }