using System;

using System.Xml.Serialization;

using System.IO;

using System.Text;

using System.Collections.Generic;

​

​

public class Program

{

    public static void Main()

    {

        using(var stream = new MemoryStream()){

            XmlSerializer xmlSer = new XmlSerializer(typeof(Quotation));

            xmlSer.Serialize(

                stream,

                new Quotation(){

                    QuotationHeader = new QuotationHeader() { QuotationNumber = "42870/09/19" },

                    QuotationItems = new List<QuotationItem> {

                        new QuotationItem { Item = "01", 

                                           QuotationItemBom = new List<QuotationItemBOM> {

                                               new QuotationItemBOM {EntityDescription = "" }

                                           }

                                          } ,

                        new QuotationItem { Item = "02" }   

                    }

                }

            );

            stream.Position = 0;

            using (var reader = new StreamReader(stream, Encoding.UTF8))

            {

                string value = reader.ReadToEnd();

                Console.WriteLine(value);

            }

        }

    }

}

​

[Serializable]

public class Quotation

{

    public QuotationHeader QuotationHeader { get; set;}

    public List<QuotationItem> QuotationItems { get; set;}

}

​

public class QuotationHeader

{

    public string QuotationNumber {get; set;}

}

​

public class QuotationItem

{

    public string Item {get; set;}

    public List<QuotationItemBOM> QuotationItemBom { get; set;}

}

​

public class QuotationItemBOM 

{

    public string EntityDescription {get; set;}

    public string RowNum {get; set;}

    public string Code  {get; set;}

    public double Qty  {get; set;}

    public bool IsBomHole  {get; set;}

    public string HoleDescription {get; set;}

}

​