With the help of XmlSerializer we can convert the list of C# objects to XML document. Below is the example of converting your array list to XML.

First of all we need to add below two namespaces to the page.

using System.Xml.Serialization;
using System.IO;

The second step is to prepare your array list. In my example i am creating a class of Book with some attributes like Name of the book, Author of the Book etc.

    [Serializable]
    public class Book
    {
        public string Name { get; set; }
        public string Author { get; set; }
        public string Publisher { get; set; }
        public int Pages { get; set; }
        public decimal Price { get; set; }
    }

The next step is to add some values to this class. Here i am creating a array of this class and adding 3 books to the array. The code is as below.

Book objBook = new Book();
objBook.Name = "Beginning JavaScript 4th Edition";
objBook.Author = "Paul Wilton";
objBook.Publisher = "Wrox";
objBook.Pages = 200;
objBook.Price = (decimal)35.34;

Book objBook_1 = new Book();
objBook_1.Name = "Head First C#";
objBook_1.Author = "Andrew Stellman";
objBook_1.Publisher = "o reilly";
objBook_1.Pages = 365;
objBook_1.Price = (decimal)23.46;

Book objBook_2 = new Book();
objBook_2.Name = "RESTful Web Services";
objBook_2.Author = "Leonard Richardson";
objBook_2.Publisher = "o reilly";
objBook_2.Pages = 200;
objBook_2.Price = (decimal)235.34;

Book[] bookArry = new Book[3];

bookArry[0] = objBook;
bookArry[1] = objBook_1;
bookArry[2] = objBook_2;

Now I have a array of class book which i want to convert to XML. Just use below sample code to convert your array to XML.

XmlSerializer Book_Serializer = new XmlSerializer(bookArry.GetType());
StringWriter Writer = new StringWriter();
Book_Serializer.Serialize(Writer, bookArry);
string strXML = Writer.ToString();

And finally the output of above example is as below.

<?xml version="1.0" encoding="utf-16"?>
<ArrayOfBook xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Book>
    <Name>Beginning JavaScript 4th Edition</Name>
    <Author>Paul Wilton</Author>
    <Publisher>Wrox</Publisher>
    <Pages>200</Pages>
    <Price>35.34</Price>
  </Book>
  <Book>
    <Name>Head First C#</Name>
    <Author>Andrew Stellman</Author>
    <Publisher>o reilly</Publisher>
    <Pages>365</Pages>
    <Price>23.46</Price>
  </Book>
  <Book>
    <Name>RESTful Web Services</Name>
    <Author>Leonard Richardson</Author>
    <Publisher>o reilly</Publisher>
    <Pages>200</Pages>
    <Price>235.34</Price>
  </Book>
</ArrayOfBook>

This is the example of array to xml asp.net, folks give me your feedback to improve quality of blog.