返回元组的EF选择 [英] Return Tuple from EF select

问题描述

我如何可以检索元组在选择使用EF4？

How can I retrieve Tuples at Select using EF4?

        var productCount = (from product in context.products
                    select new Tuple<Product, int>(product, products.Orders.Count));

或

        var productCount = (from product in context.products
                    select Tuple.Create(product, products.Orders.Count));

实体框架说，不能使用非空构造函数第一种情况下，并不能识别Tuple.Create法第二。

Entity framework says that cant use not empty constructor for first case, and not recognize Tuple.Create method for second.

推荐答案

如何切换到LINQ到对象的投影：

How about switching to LINQ-to-Objects for the projection:

var productCount = from product in context.products
                select new {Product = product, Count = products.Orders.Count };
var final = from item in productCount.AsEnumerable()
            select Tuple.Create(item.Product, item.Count);

这篇关于返回元组的EF选择的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！