我对客户及其订单有以下代码。我想列出所有的客户ID和相应的订单数量。我如何使用LINQ实现它?LINQ - 嵌套计数问题
注意:我是LINQ和var的新手。
protected void Page_Load(object sender, EventArgs e)
{
List<Order> orderListForCus1 = new List<Order>();
Order ord1 = new Order(1, new DateTime(2011, 9, 1));
Order ord2 = new Order(1, new DateTime(2011, 8, 1));
orderListForCus1.Add(ord1);
orderListForCus1.Add(ord2);
Customer cus1 = new Customer();
cus1.CustomerID = 1;
cus1.OrderList = orderListForCus1;
List<Customer> customerRecordsBook = new List<Customer>();
customerRecordsBook.Add(cus1);
var orderCounts = from c in customerRecordsBook
select new { c.CustomerID, OrderCount = c.OrderList.Count() };
}
你已经有了。你在问什么? – SLaks
使用普通的'foreach'。 – SLaks