WebApp.CustomersExtension.Filter C# (CSharp) Метод

        public static Func<Customer, bool> Filter(FilterParams filter)
        {
            Func<Customer, bool> func = (x) =>
            {
                bool result = true;
                if (filter.CityId.HasValue)
                {
                    result &= x.CityId == filter.CityId.Value;
                }

                if (filter.DistrictIds.Length > 0)
                {
                    result &= filter.DistrictIds.All(districtId => x.DistrictToClients.Any(d => d.DistrictId == districtId));//x.DistrictToClients == filter.DistrictId.Value;
                }

                if (filter.HouseTypeIds.Length > 0)
                {
                    result &= filter.HouseTypeIds.All(f => x.TypesHousingToCustomers.Any(type => type.TypesHousingId == f));
                }

                if (filter.PriceFrom.HasValue && filter.PriceTo.HasValue)
                {
                    result &= x.MinSum <= filter.PriceFrom.Value && x.MaxSum >= filter.PriceTo.Value;
                }
                else if (filter.PriceFrom.HasValue)
                {
                    result &= x.MinSum <= filter.PriceFrom.Value;
                }
                else if (filter.PriceTo.HasValue)
                {
                    result &= x.MaxSum >= filter.PriceTo.Value;
                }

                if (filter.IsArchived.HasValue)
                {
                    result &= x.IsArchive == filter.IsArchived.Value;
                }
                else
                {
                    result &= x.IsArchive == false;
                }

                if (filter.IsSiteAccessOnly.HasValue && filter.IsSiteAccessOnly.Value)
                {
                    result &= x.IsSiteAccess == true;
                }
                return result;
            };

            return func;
        }
    }