Comments by boyliberal2007 (Top 4 by date)

thanks you, I have done.

QSEntities dt = new QSEntities();
DataTable dt1 = new DataTable("table");
dt1.Columns.Add("student_Id");
dt1.Columns.Add("student_name");
dt1.Columns.Add("nameofacademic");
var query = from s in dt.tableone
join n in dt.tabletwo on s.academic_yearid equals ad.academic_yearid
select new
{
student_Id = s.student_Id,
student_name = s.student_name,
nameofacademic = n.nameofacademic,

};
foreach (var x in query)
{
DataRow dr = dt1.NewRow();
//DataRow row = new DataRow();
dr["student_Id"] = x.student_Id;
dr["student_name"] = x.student_name;
dr["nameofacademic"] = x.nameofacademic;
dt1.Rows.Add(dr);
dt1.AcceptChanges();
}
grdF_sinhvien.DataSource = dt1;