How to get Data From Sql Database in Xml Format and from that Xml Fill DataSet

I am trying to get data from sql server in xml format and form that xml filling dataset

here is my Simple Query :-

       SELECT * FROM TblAcademicYear FOR XML RAW('AcademicYear') , ELEMENTS;

this query give me following output :-

 <AcademicYear>
    <AcademicYearId>3</AcademicYearId>
    <AcademicYearName>دو ‌ہزار ‌پندرہ</AcademicYearName>
    <StartingYear>2015-01-01</StartingYear>
   <EndingYear>2015-12-31</EndingYear>
   <Comments>دو ‌ہزار ‌پندرہ ‌کا ‌تعلیم ‌سال</Comments>
  <RCO>2014-07-02</RCO>
  <UserID>2</UserID>
</AcademicYear>

And my C# Code is :-

        SqlConnection conn = new SqlConnection(ConnectionString);
        SqlCommand cmd = new SqlCommand();
         System.Xml.XmlReader xmlreader;
        try
            {
                cmd.Connection = conn;
                conn.Open();
                cmd.CommandText = _Query;
                xmlreader = cmd.ExecuteXmlReader();
                conn.Close();

                DataSet ds = new DataSet();
                dt.Columns.Add("AcademicYearId", typeof(string));
                dt.Columns.Add("AcademicYearName", typeof(string));
                dt.Columns.Add("StartingYear", typeof(string));
                dt.Columns.Add("EndingYear", typeof(string));
                dt.Columns.Add("Comments", typeof(string));
                dt.Columns.Add("RCO", typeof(string));
                dt.Columns.Add("UserID", typeof(string));
                ds.Tables.Add(dt);
                ds.ReadXml(xmlreader);
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (conn.State != ConnectionState.Closed)
                {
                    conn.Close();
                }
            }

and the above code run perfectly but it does not give me the data Any help would be appreciated .....