I’ve try to loop and from the below code, The problem is when it loop back to “IEnumerable selectedRows =”. The value of DateStart and DateEnd remain the same “9/1/2003 2:00:00” and “9/1/2003 2:59:00” respectively as its initial value. Why the “IEnumerable selectedRows =” do not update the DateTime value? Please help and thank you.

IEnumerable<DataRow> selectedRows = dtData.AsEnumerable().Where(row => (row.Field<DateTime>("Date") >= DateStart) && row.Field<DateTime>("Date") <= DateEnd);


  foreach (DataRow row in selectedRows)
  {

     //Do some stuffs

  }
  
  //store the result in DataTable
  DataRow dtDataRowResult = dtDataResult.NewRow();
  dtDataRowResult[0] = DateStart;
  dtDataRowResult[1] = result1;
  dtDataRowResult[2] = result2;
  dtDataResult.Rows.Add(dtDataRowResult);

  //when code go this line below, it should be added one hour from the previous hour, so now it is “9/1/2003 3:00:00”
  DateStart = DateStart.AddHours(1);
 //and the DateEnd should be added to “9/1/2003 3:59:00”
  DateEnd = DateStart + TimeSpan.FromMinutes(59);
 //The problem is when it loop back to “IEnumerable<DataRow> selectedRows =”. The value of DateStart and DateEnd remain the same “9/1/2003 2:00:00” and “9/1/2003 2:59:00” respectively as the initial value. Why the “IEnumerable<DataRow> selectedRows =” not updated the DateTime value? Please help and thank you.
  }

The below is the screenshot image of the example code