假设您有以下简单对象：
class Order
{
public Customer[] Customers { get; set; }
}
class Customer
{
public SaleLine[] SaleLines { get; set; }
}
class SaleLine
{
public Tax[] MerchTax { get; set; }
public Tax[] ShipTax { get; set; }
}
class Tax
{
public decimal Rate { get; set; }
public decimal Total { get; set; }
}
有了这些对象,我希望能够获得整个订单上使用的所有独特税率的清单,包括商品和运费税率.
var TaxRates = MyOrder.Customers
.SelectMany(customer => customer.SaleLines)
.SelectMany(saleline => saleline.MerchTax)
.GroupBy(tax => tax.Rate)
.Select(tax => tax.First().Rate
如何获得包含商品和运费的唯一税率列表的列表？
解决方法
听起来你想要这个：
var TaxRates = MyOrder.Customers
.SelectMany(customer => customer.SaleLines)
.SelectMany(saleline => saleline.MerchTax.Concat(saleline.ShipTax))
.GroupBy(tax => tax.Rate)
.Select(group => group.Key);
基本上,更改是对Concat的调用,它将两个序列连接在一起.
