linq读写dt

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Linq Lambda 匿名方法查找DataRow
查找DataTable中的DataRow

DataRow dr = dt.Rows.Find(gv.DataKeys[e.RowIndex]["id"].ToString());dr["flag"] = "0";

Linq

IEnumerable<DataRow> q = from dr in dt.AsEnumerable()                         where dr.Field<int>("id").ToString() == gv.DataKeys[i]["id"].ToString()                         select dr;foreach (DataRow dr in q)    dr["flag"] = "0";

Lambda

IEnumerable<DataRow> q = dt.AsEnumerable().Where<DataRow>(r => (r.Field<int>("id").ToString() == gv.DataKeys[e.RowIndex]["id"].ToString()));            foreach (DataRow dr in q)                dr["flag"] = "0";

匿名方法

IEnumerable<DataRow> q = dt.AsEnumerable().Where<DataRow>(delegate(DataRow r) { return r["id"].ToString() == gv.DataKeys[i]["id"].ToString(); });                    foreach (DataRow dr in q)                         dr["flag"] = "0";

1.查询DataRow

1 IEnumerable q1 = from r in dt.AsEnumerable()
2 where r.Field(“ID”) % 2 == 0
3 select r;

2.查询某个字段

var query2 =
from pl in dt.AsEnumerable( )
select pl.Field(“Name”);

Array Linq查询

1 int[] values = { 2,9,5,0,3,7,1,4,8,5};  2             var filtered =  3                 from value in values  4                 where value > 4  5                 select value;

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