linq - LINQ - 按 lambda 表达式分组

Question

说我有以下内容：

var OrderCounts = from o in Orders
                  group o by o.CustomerID into g
                  select new {
                         CustomerID = g.Key,
                         TotalOrders = g.Count()
                  };

如何将其转换为 Lambda 表达式

Answer 1

var OrderCounts = customers
        .GroupBy (o => o.CustomerID)
        .Select (o => new { CustomerID = o.Key, TotalOrders = o.Count () })