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LINQ - 从表格中删除非区别行
原标题:LINQ - Strip non-distinct rows from a table
  • 时间:2012-05-25 19:23:07
  •  标签:
  • .net
  • linq

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?

最佳回答
    dtSuplr = (from suplr in dtSuplr.AsEnumerable()
                   select suplr).Distinct().CopyToDataTable();
问题回答

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 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> 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:

  1. create a DataTable
  2. create columns with DataColumnCollection.Add Method (String, Type)
  3. loop through the data
  4. add a new row for each item with the DataRowCollection.Add Method (Object[])




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