DataTable NewRow สามารถเพิ่มข้อมูลได้ทีละชุดรึป่าวครับ ประมาณว่าเอาไปเพิ่มต่อของข้อมูลที่มีอยู่แล้ว

DataTable dt = new DataTable();
DataRow dr;

//*** Column ***//
dt.Columns.Add("CustomerID");
dt.Columns.Add("Name");
dt.Columns.Add("Email");
dt.Columns.Add("CountryCode");
dt.Columns.Add("Budget");
dt.Columns.Add("Used");

//*** Rows ***//
dr = dt.NewRow();
dr["CustomerID"] = "C001";
dr["Name"] = "Win Weerachai";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "TH";
dr["Budget"] = "1000000";
dr["Used"] = "600000";
dt.Rows.Add(dr);

//*** Rows ***//
dr = dt.NewRow();
dr["CustomerID"] = "C002";
dr["Name"] = "John Smith";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "EN";
dr["Budget"] = "2000000";
dr["Used"] = "800000";
dt.Rows.Add(dr);

//*** Rows ***//
dr = dt.NewRow();
dr["CustomerID"] = "C003";
dr["Name"] = "Jame Born";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "US";
dr["Budget"] = "3000000";
dr["Used"] = "600000";
dt.Rows.Add(dr);

//*** Rows ***//
dr = dt.NewRow();
dr["CustomerID"] = "C004";
dr["Name"] = "Chalee Angel";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "US";
dr["Budget"] = "4000000";
dr["Used"] = "100000";
dt.Rows.Add(dr);

DataTable dt2 = dt1;
DataRow dr;

//*** Rows ***//
dr = dt2.NewRow();
dr["CustomerID"] = "C001";
dr["Name"] = "Win Weerachai";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "TH";
dr["Budget"] = "1000000";
dr["Used"] = "600000";
dt2.Rows.Add(dr);

//*** Rows ***//
dr = dt2.NewRow();
dr["CustomerID"] = "C002";
dr["Name"] = "John Smith";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "EN";
dr["Budget"] = "2000000";
dr["Used"] = "800000";
dt2.Rows.Add(dr);

//*** Rows ***//
dr = dt2.NewRow();
dr["CustomerID"] = "C003";
dr["Name"] = "Jame Born";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "US";
dr["Budget"] = "3000000";
dr["Used"] = "600000";
dt2.Rows.Add(dr);

//*** Rows ***//
dr = dt2.NewRow();
dr["CustomerID"] = "C004";
dr["Name"] = "Chalee Angel";
dr["Email"] = "[email protected]";
dr["CountryCode"] = "US";
dr["Budget"] = "4000000";
dr["Used"] = "100000";
dt2.Rows.Add(dr);

                    var qs6 = from p in db.Students
                              where p.SubjectID == txtSubID.Text.Trim() && p.Section == txtSec.Text.Trim()
                              select p.StudentID;

                    var student = from s in db.StudentTimeTables
                                  where s.DateExam == txtDateExam.Text.Trim()
                                  select s.StudentID;

                    foreach (var c in qs6)
                    {
                        foreach (var d in student)
                        {
                            if (Convert.ToInt32(c) == Convert.ToInt32(d))
                            {                                      
                                        DataTable dt = new DataTable();
                                        dt.Columns.Add(new DataColumn("id"));
                                        DataRow dr = dt.NewRow();
                                        dr["id"] = d;
                                        dt.Rows.Add(dr);                                       
                             }                                 
                        }                                
                   }                   

 var qs6 = from p in db.Students
           where p.SubjectID == txtSubID.Text.Trim() && p.Section == txtSec.Text.Trim()
           select p.StudentID;

 var student = from s in db.StudentTimeTables
               where s.DateExam == txtDateExam.Text.Trim()
               select s.StudentID;


DataTable dt = new DataTable();
dt.Columns.Add(new DataColumn("id"));

 foreach (var c in qs6)
 {
     foreach (var d in student)
     {
         if (Convert.ToInt32(c) == Convert.ToInt32(d))
         {                                      
                     DataRow dr = dt.NewRow();
                     dr["id"] = d;
                     dt.Rows.Add(dr);                                       
          }                                 
     }                                
}