c# - LINQ 分组依据不起作用

Question

我有这个 LINQ 查询:

from p in Products
join c in Categories on p.CategoryID equals c.CategoryID
group p by p.Category into prices
select new {price = prices.Average(p => p.UnitPrice), name = p.Category.CategoryName }

我得到的错误是:

The name 'p' does not exist in the current context

为什么我不能在这里访问p？我应该怎么做才能解决这个问题？

Answer 1

您可以使用键:

...
group p by p.Category into prices
select new 
{
    price = prices.Average(p => p.UnitPrice), 
    name = prices.Key.CategoryName 
}