using System;

using System.IO;

using System.Xml.Serialization;

using System.Text;

​

    [XmlType(TypeName="XmlAble"),Serializable]

    public class XmlAble

    {

        [XmlElement]

        public DateTime MyDate { get { return MyDateField; } set { MyDateField = value; MyDateSpecified = true; } }

        private DateTime MyDateField;

​

        [XmlIgnore]

        public bool MyDateSpecified

        {get;set;}

​

    }

​

public class Program

{

    public static void Main()

    {

        var myOb = new XmlAble();

        Console.WriteLine("Enter 'T' to include MyDateSpecified = true:");

        myOb.MyDateSpecified = Console.ReadLine().StartsWith("T");

        using (var strm = new MemoryStream())

        {

            new XmlSerializer(typeof(XmlAble)).Serialize(strm, myOb);

            Console.WriteLine(Encoding.UTF8.GetString(strm.ToArray()));

        }

    }

}