linq Group By from DataTable
本文关键字:DataTable from By Group linq | 更新日期: 2023-09-27 18:31:57
我有这样的数据表
谢谢鲍勃·韦尔的帮助
什么是 (选择(X,i) 在你的 linq 中的意思,但是当我在表格中犯了一个错误时我有这个
No | Size | Type | FB | FP
----------------------------------------
100 | 2 | typeA | FB1 | A1
101 | 3 | typeB | FB1 | A1
101 | 4 | typec | FB1 | A1
103 | 4 | typeC | FB2 | A2
103 | 5 | typeD | FB2 | A2
103 | 6 | typeE | FB2 | A2
我想拥有这样的东西
No | Size | Type | FB | FP
---------------------------------
100 | 2 | typeA | FB1 | A1
101 | 3 | typeB | FB1 | A1
| 4 | typec | |
103 | 4 | typeC | FB2 | A2
| 5 | typeD | |
| 6 | typeE | |
我该怎么做?我可以使分组依据
var result = from row in cableDataTable.AsEnumerable()
group row by new
{
FB = row.Field<string>("FB"),
FP = row.Field<string>("FP"),
Size = row.Field<int>("Size"),
Type = row.Field<int>("Type"),
no= row.Field<int>("no"),
} into g
select new
{
FB = g.Key.FB,
FP = g.Key.FP,
Size = g.Key.Size,
Type = g.Key.Type
no= g.Key.no };
但它不能给出结果
感谢您的关注
这个怎么样:
// First declare a conversion from the DataTable to an anon type
var rows = cableDataTable.AsEnumerable()
.Select(x => new {
Size = x.Field<int>("Size"),
Type= x.Field<string>("Type"),
FB = x.Field<string>("FB"),
FP = x.Field<string>("FP")
});
// Now use group by, ordering and select many to select the rows
var result = rows.GroupBy (row => new {row.FB, row.FP} )
.OrderBy (g => g.Key.FB)
.ThenBy(g => g.Key.FP)
.SelectMany(g => g.OrderBy(row => row.Size)
.Select((x,i) =>
new {
Size = x.Size,
Type = x.Type,
FB = (i==0) ? x.FB : null,
FP= (i==0) ? x.FP : null
}));
您可以将 linq 查询用作 var result = cableDataTable.AsEnumerable()。GroupBy(g => new { g.FB, g.FP}).选择(x => x);