C# for loop inside deep XML serialization

Question

I am trying to make a deep nested XML file in which I want to insert some data from another file.

How it looks right now:

  <Documents Count="1">
    <Item DATE="2020-09-01" CREATEDBY="TestUser">
      <Row ITEMID="" ACTIVE="" />
    </Item>
  </Documents>

I want it to look like this:

  <Documents Count="1">
    <Item DATE="2020-09-01" CREATEDBY="TestUser">
      <Row ITEMID="" ACTIVE="" />
      <Row ITEMID="" ACTIVE="" />
      <Row ITEMID="" ACTIVE="" />
      <Row ITEMID="" ACTIVE="" />
    </Item>
  </Documents>

And the problem is that the node "Item" has to have many rows inside of it (node "Row"), and I want to fill data for it from another file by reading it's every line and to do that I need a for loop. I am stuck, because it won't let me add a for loop in there, is there a way to somehow insert a for loop in there?

Thanks.

Here's the code that I have written so far:

class Program
{
    static void Main(string[] args)
    {
        var xmlData = new XmlData();

        xmlData.documents.documentsItem.Add(new DocumentsItem()
        {
            DATE = DateTime.Now.ToString("yyyy-MM-dd"),
            CREATEDBY = "TestUser",

            documentsRow = new List<DocumentsRow>()
            {
            //<-- I want to insert a 'for' loop in here, but it won't allow me to do that
                new DocumentsRow()
                {
                    ITEMID = "",
                    ACTIVE = "",
                }
            }
            });
        xmlData.documents.Count = xmlData.documents.documentsItem.Count;

        using (StreamWriter sw = new StreamWriter(@"c:\a\test.xml", false, Encoding.UTF8))
        {
            new XmlSerializer(typeof(XmlData)).Serialize(sw, xmlData);
        }

    }
}


public class XmlData
{
    [XmlElement("Documents")]
    public Documents documents = new Documents();

    [XmlIgnore]
    public DocumentsRow documentsRow = new DocumentsRow();
}


public class Documents
{
    public Documents()
    {
        documentsItem = new List<DocumentsItem>();
    }

    [XmlAttribute]
    public int Count { get; set; }

    [XmlElement("Item")]
    public List<DocumentsItem> documentsItem { get; set; }
}

public class DocumentsItem
{
    public DocumentsItem()
    {
        documentsRow = new List<DocumentsRow>();
    }

    [XmlAttribute]
    public string DATE { get; set; }

    [XmlAttribute]
    public string CREATEDBY { get; set; }

    [XmlElement("Row")]
    public List<DocumentsRow> documentsRow { get; set; }
}

public class DocumentsRow
{
    [XmlAttribute]
    public string ITEMID { get; set; }

    [XmlAttribute]
    public string ACTIVE { get; set; }
}

Answer 1

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Xml.Serialization;

namespace ConsoleApp31
{
    class Program
    {
        static void Main(string[] args)
        {
            var xmlData = new XmlData();

            xmlData.documents.documentsItem.Add(new DocumentsItem()
            {
                DATE = DateTime.Now.ToString("yyyy-MM-dd"),
                CREATEDBY = "TestUser",

                documentsRow = GetDocuments(100)
            });
            xmlData.documents.Count = xmlData.documents.documentsItem.Count;

            using (StreamWriter sw = new StreamWriter(@"c:\a\test.xml", false, Encoding.UTF8))
            {
                new XmlSerializer(typeof(XmlData)).Serialize(sw, xmlData);
            }

        }
        private static List<DocumentsRow> GetDocuments(int number)
        {
            var documents = new List<DocumentsRow>();
            for (int i = 0; i <= number; i++)
            {
                documents.Add(new DocumentsRow() { ITEMID = "", ACTIVE = "" });
            }
            return documents;
        }
    }
    public class XmlData
    {
        [XmlElement("Documents")]
        public Documents documents = new Documents();

        [XmlIgnore]
        public DocumentsRow documentsRow = new DocumentsRow();
    }


    public class Documents
    {
        public Documents()
        {
            documentsItem = new List<DocumentsItem>();
        }

        [XmlAttribute]
        public int Count { get; set; }

        [XmlElement("Item")]
        public List<DocumentsItem> documentsItem { get; set; }
    }

    public class DocumentsItem
    {
        public DocumentsItem()
        {
            documentsRow = new List<DocumentsRow>();
        }

        [XmlAttribute]
        public string DATE { get; set; }

        [XmlAttribute]
        public string CREATEDBY { get; set; }

        [XmlElement("Row")]
        public List<DocumentsRow> documentsRow { get; set; }
    }

    public class DocumentsRow
    {
        [XmlAttribute]
        public string ITEMID { get; set; }

        [XmlAttribute]
        public string ACTIVE { get; set; }
    }
}