public DataTable CheckPreviousGPXTrackPointsNew(int UserId, int SchoolId, int ClassId, DataTable dtNew) { DataTable _dt = null; foreach (DataRow item in dtNew.Rows) { int ele = 0; try { ele = int.Parse(Convert.ToString(item["ele"]), System.Globalization.CultureInfo.InvariantCulture); } catch { } item["ele"] = ele; } DataTable result = objStudent.CheckGPXFileTable(dtNew, ClassId, UserId); if (result != null) { DataView dv = result.DefaultView; dv.Sort = "time asc"; _dt = dv.ToTable(); } return(_dt); }