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c#datatableienumerable

Convert DataTable to IEnumerable<T>


I am trying to convert a DataTable to an IEnumerable. Where T is a custom type I created. I know I can do it by creating a List<T> but I was thinking if there is a slicker way to do it using IEnumerable. Here is what I have now:

private IEnumerable<TankReading> ConvertToTankReadings(DataTable dataTable)
{
    var tankReadings = new List<TankReading>();
    foreach (DataRow row in dataTable.Rows)
    {
        var tankReading = 
              new TankReading
              {
                  TankReadingsID = Convert.ToInt32(row["TRReadingsID"]),
                  TankID = Convert.ToInt32(row["TankID"]),
                  ReadingDateTime = Convert.ToDateTime(row["ReadingDateTime"]),
                  ReadingFeet = Convert.ToInt32(row["ReadingFeet"]),
                  ReadingInches = Convert.ToInt32(row["ReadingInches"]),
                  MaterialNumber = row["MaterialNumber"].ToString(),
                  EnteredBy = row["EnteredBy"].ToString(),
                  ReadingPounds = Convert.ToDecimal(row["ReadingPounds"]),
                  MaterialID = Convert.ToInt32(row["MaterialID"]),
                  Submitted = Convert.ToBoolean(row["Submitted"]),
              };

        tankReadings.Add(tankReading);
    }
    return tankReadings.AsEnumerable();
}

The key part being I am creating a List<T> then returning it using AsEnumerable().


Solution

  • Nothing wrong with that implementation. You might give the yield keyword a shot, see how you like it:

    private IEnumerable<TankReading> ConvertToTankReadings(DataTable dataTable)
        {
            foreach (DataRow row in dataTable.Rows)
            {
                yield return new TankReading
                                      {
                                          TankReadingsID = Convert.ToInt32(row["TRReadingsID"]),
                                          TankID = Convert.ToInt32(row["TankID"]),
                                          ReadingDateTime = Convert.ToDateTime(row["ReadingDateTime"]),
                                          ReadingFeet = Convert.ToInt32(row["ReadingFeet"]),
                                          ReadingInches = Convert.ToInt32(row["ReadingInches"]),
                                          MaterialNumber = row["MaterialNumber"].ToString(),
                                          EnteredBy = row["EnteredBy"].ToString(),
                                          ReadingPounds = Convert.ToDecimal(row["ReadingPounds"]),
                                          MaterialID = Convert.ToInt32(row["MaterialID"]),
                                          Submitted = Convert.ToBoolean(row["Submitted"]),
                                      };
            }
    
        }
    

    Also the AsEnumerable isn't necessary, as List<T> is already an IEnumerable<T>