using System;    

using System.IO;

using System.Xml.Serialization;

public class Program

{

    public static void Main()

    {

        var xml = "<?xml version=\"1.0\"?><SampleXml><SampleValue>sample</SampleValue></SampleXml>";

        var serializerForInternal = new XmlSerializer(typeof(InternalSampleXml));

        using (TextReader reader = new StringReader(xml))

        {

            var result = (InternalSampleXml)serializerForInternal.Deserialize(reader);

            Console.WriteLine(result.SampleValue);

        }

    }

    [System.SerializableAttribute()]

    internal class InternalSampleXml

    {

        internal string SampleValue{ get; set; }

    }

}