林克加入并排序

Question

我在一个表中有文件，在另一个表中有文件操作。我想获取 Jeff 对其执行操作的最新文件，该文件的状态为 4。在SQL中，它看起来像这样：

SELECT TOP 1 files.* 
FROM files 
LEFT OUTER JOIN fileActions ON files.FileId = fileActions.FileId
WHERE fileActions.ActionTaker = 'Jeff'
    AND files.FileStatus = 4
ORDER BY fileActions.ActionDate DESC

我将如何在 Linq 中表达相同的查询？

我已经尝试了很多东西，但我什至无法编译它。我觉得这是我迄今为止最接近的一次，但显然"top"不是一个 linq 语法词，所以我有一个很好的方法：

var file = from f in context.Files
           join fa in context.FileActions on f.FileId equals fa.FileId
           where fa.ActionTaker == "Jeff"
           where f.FileStatus == 4
           orderby fa.ActionDate descending
           select top 1 f;

任何帮助，不胜感激。

Answer 1

如果我理解你的问题...

 var file = (from f in context.Files
             join fa in context.FileActions on f.FileId equals fa.FileId
             where fa.ActionTaker == "Jeff" && f.FileStatus == 4
             orderby fa.ActionDate descending
             select new { Value1 = fa.Id, Value2 = f.Id }).FirstOrDefault();

Answer 2

试试这个：

var file = (from f in context.Files
            join fa in context.FileActions on f.FileId equals fa.FileId
            where fa.ActionTaker == "Jeff" && f.FileStatus == 4
            orderby fa.ActionDate descending
            select f).FirstOrDefault();

Answer 3

试试这个

var file = (from f in context.Files
           join fa in context.FileActions on f.FileId equals fa.FileId
           where fa.ActionTaker == "Jeff"
           && f.FileStatus == 4
           orderby fa.ActionDate descending
           select  f).first();