public void PopulateExamDetails() { var dt = new DataTable(); dt.Columns.Add("SN"); dt.Columns.Add("NAME"); dt.Columns.Add("SCHOOL"); dt.Columns.Add("EXAMINATION"); dt.Columns.Add("FEES"); dt.Columns.Add("EXAMID"); var Exams = DropDownManager.GetRegisteredStudents(); int sn = 0; foreach (var item in Exams) { string id = item.StudentID.ToString(); string Name = item.StudentName; string schoolName = item.SchoolName; string Exam = item.ExamCode; string ExamId = item.ExamId.ToString() + "," + item.StudentID.ToString() + "," + item.SchoolId.ToString(); string Fee = item.Fee; sn++; dt.Rows.Add(sn, Name, schoolName, Exam, Fee, ExamId); } gvSubject.DataSource = dt; gvSubject.DataBind(); }