试图从 dt 中选择不同的行, 并将结果放回相同的 dt 中。 我想这可以在一个语句中完成。 下面我尝试的是 :
dt = (DataTable)((from row in dt.AsEnumerable() select row.Field<string>("VNDR_ID")).Distinct().ToList());
我怎样才能达到这个目的?
试图从 dt 中选择不同的行, 并将结果放回相同的 dt 中。 我想这可以在一个语句中完成。 下面我尝试的是 :
dt = (DataTable)((from row in dt.AsEnumerable() select row.Field<string>("VNDR_ID")).Distinct().ToList());
我怎样才能达到这个目的?
dtSuplr = (from suplr in dtSuplr.AsEnumerable()
select suplr).Distinct().CopyToDataTable();
LINQ 声明
(from row in dt.AsEnumerable() select row.Field<string>("VNDR_ID")).Distinct()
返回 IEnumberable<string>
返回 DataTable
,所以投影失败。
您需要将结果放入另一个 < code> Datatable code> 的原因吗? 我只需要使用查询返回的 < code> > Ienumberable , 或者将其转换为 List<string>
和 ToList ()
, 如果您想要立即评估查询的内容(以便您可以更改 dt
的内容) 。
您无法将它投入数据表。 Linq 将最终根据您选择的结果输出 Ienumberable<string>
。 要将此装入数据表, 您必须:
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