Linq to SQL Group by和Select中的和

Question

我需要将该SQL查询转换为Linq：

SELECT
    SUM([ArticleAmount]) as amount
    ,[ArticleName]
FROM [DB].[dbo].[OrderedArticle]

group by articlename

order by amount desc

我尝试了以下代码，但在“ a.ArticleName”处收到错误消息，提示“ ArticleName”的定义将丢失。

var sells = orderedArt
            .GroupBy(a => a.ArticleName)
            .Select(a => new {Amount = a.Sum(b => b.ArticleAmount),Name=a.ArticleName})
            .OrderByDescending(a=>a.Amount)
            .ToList();

你们中有人有人知道如何解决此问题吗？

谢谢你的帮助！

Answer 1

您收到此错误是因为分组未返回，IEnumerable<OrderedArticle>但IEnumerable<IGrouping<string, OrderedArticle>>

您需要更改代码以使用a.Key：

var sells = orderedArt
    .GroupBy(a => a.ArticleName)
    .Select(a => new { Amount = a.Sum(b => b.ArticleAmount), Name = a.Key})
    .OrderByDescending(a => a.Amount)
    .ToList();