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c#csvhelper

CSV writer cannot write List of objects

I use CSV writer and it work great for most part. When I try to write the object which has a list, it ignores writing the list only. for eg.below, it writes all the attributes of the Trade object except the Wave which is a List of Wave objects

my class trade has following including a list Wave.

     class Trade
    {
        public string  symbol { get; set; }
        public bool isOpen { get; set; }
        public DateTime OpenTime { get; set; }
        public DateTime CloseTime { get; set; }
        public double mfe { get; set; }
        public double mae { get; set; }
        public double entryPrice { get; set; }
        public double exitprice { get; set; }
        public TradeP TradeSignal { get; set; }
        public string  comments { get; set; }
        public int  Days2Stop { get; set; }
        public double TimeBreakout { get; set; }
        public double r { get; set; }
        public int  daysreach1r { get; set; }
        public int daysreach9x50 { get; set; }
        public double maetill1r { get; set; }
        public bool Day1ClosedDown { get; set; }
        public List<Wave> Waves { get; set; }

    }
     // write all the trade objects
            using (System.IO.StreamWriter file =
new System.IO.StreamWriter(@"C:\temp\" + DateTime.Now.ToString("yyyyMMdd") + "traderesults.txt", true))
            {
                var csv = new CsvWriter(file);
                csv.WriteRecords(Trades);

            }

enter image description here

In the screenshot above, you can see the csv writer prints all the object attributes. its pretty long but at the end it does not print the attribute of the Wave objects

Solution

  • CSV file is flat. How would you represent such record, if you had to create a file manually. You would have to repeat records. Which does not make sense, so library is doing a right thing here by ignoring Waves.

    Workaround would be to have another property in your class that returns you the comma separated values for a property in Wave object, say Prop1 (string).

    class Trade {
  //..
  public string WaveCSV {
    get {
      return string.Join(",", Waves.Select(w => w.Prop1).ToArray()); 
    }
  }
}

    You will need to qualify WaveCSV with " so that comma within the value doesn't harm, or use a different separator altogether.

    Edit:

    If you need more than one property, then you can override ToString() in Wave class, return whatever you want, and use w.ToString() instead.