Question

select    
  count(di.field1) as myCount,
  di.field2
  from di
group by  di.field2

我试图理解这个概念：

 group di.field2 by new { di.field1, di.field2 } into g
       select new
          {
             documentID = g.Key.field2,
             docCount = g.Count(????)
          });

我如何获得field1计数的值？

Answer 1

也许是这样的：

group di by di.field2 into g
       select new
          {
             documentID = g.Key,
             docCount = g.Select(c => c.field1).Count()
          });

Answer 2

    from p in di
    group p by p.field2 into g 
    select new { field2 = g.Key, field2Count = g.Count() };

检查一下。，这应该可行

Answer 3

您是否需要进行分组才能获得字段数？你不能这样做：

var count=di.field1.Count;

Linq集团。关键字段数

3 个答案: