Export nested object to CSV

Question

I'm using CsvHelper library to export data to CSV. I'm facing a difficulty on creating a map for the nested list object.

public class Level1
{
    public int Prop1 { get; set; }
    public string Prop2 { get; set; }
    public Level2 Level2 { get; set; }
}

public class Level2
{
    public int Prop3 { get; set; }
    public string Prop4 { get; set; }
    public List<Level3> Level3 { get; set; }
}
public class Level3
{
    public int Prop5 { get; set; }
}

As an output of the csv what want to have is:

Prop1,Prop2,Prop3,Prop4,Level3
  1  ,test ,2    , LL, , <list as ; separated>

Can anyone help me out on creating the map using CsvHelper library?

Answer 1

For nested list, you could use string.Join() to concatenate prop5, like the following code :

List<Level1> levels = new List<Level1>();
var result = levels.Select(x => new
{
    Prop1 = x.Prop1,
    Prop2 = x.Prop2,
    Prop3 = x.Level2.Prop3,
    Prop4 = x.Level2.Prop4,
    Level3 = string.Join(";", x.Level2.Level3.Select(y => y.Prop5))
}).ToList();

I hope you find this helpful.