LinQ: sub items and root in DataTable

[cuong nm]

Hi ! I have some codes below here: DataTable objTable = new DataTable(); objTable.Columns.Add("ID"); objTable.Columns.Add("Name"); objTable.Columns.Add("Root"); DataRow objrow1 = objTable.NewRow(); objrow1["ID"] = "1"; objrow1["Name"] = "1"; objrow1["Root"] = ""; objTable.Rows.Add(objrow1); objrow1 = objTable.NewRow(); objrow1["ID"] = "11"; objrow1["Name"] = "11"; objrow1["Root"] = "1"; objTable.Rows.Add(objrow1); objrow1 = objTable.NewRow(); objrow1["ID"] = "12"; objrow1["Name"] = "12"; objrow1["Root"] = "1"; objTable.Rows.Add(objrow1); objrow1 = objTable.NewRow(); objrow1["ID"] = "121"; objrow1["Name"] = "121"; objrow1["Root"] = "12"; objTable.Rows.Add(objrow1); objrow1 = objTable.NewRow(); objrow1["ID"] = "2"; objrow1["Name"] = "2"; objrow1["Root"] = ""; objTable.Rows.Add(objrow1); objrow1 = objTable.NewRow(); objrow1["ID"] = "21"; objrow1["Name"] = "21"; objrow1["Root"] = "2"; objTable.Rows.Add(objrow1); And now, how can I list item and subitems in root is 1?Please help me !!!!

MCP.NET, MCAD.NET, MCSD.NET

[Simon_Whale]

you will need to make sure that there is a reference to System.Data.DataSetExtensions in your project.

var Results = from data in objTable.AsEnumerable()
where data.Field("Root") == 1
select data

further reading Linq query on a datatable[^] Queries in LINQ to DataSet[^]

Every day, thousands of innocent plants are killed by vegetarians. Help end the violence EAT BACON

[cuong nm]

Thanks ! It return two items: 11 and 12. But sub items of 12? How can I get its?

MCP.NET, MCAD.NET, MCSD.NET

[Xiecm_China]

var list = objTable.AsEnumerable();

        var query = from l in list
            where l.Field<string>("root") == "1"
            select l;

        var result = query.Concat(from q in query
            from l in list
            where l.Field<string>("root") == q.Field<string>("id")
            select l);

        foreach (var r in result)
        {
            Console.WriteLine("value has id:{0}, root:{1}", r.Field<string>("id"), r.Field<string>("root"));
        }