conversion sql table to xml file

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["constring"].ConnectionString);
       if (con.State == ConnectionState.Closed)
       {
           con.Open();
       }
       SqlCommand cmd = new SqlCommand("select name ,user_code from tbl_user ", con);
       SqlDataAdapter da = new SqlDataAdapter(cmd);
       DataSet ds = new DataSet();
       da.Fill(ds);
       ds.Tables[0].WriteXml(@"D:\text.xml");

       if (con.State == ConnectionState.Open)
       {
           con.Close();
       }