Data Read Returning (Invalid Attempt to Read when Reader is closed)

I am trying to read an XML returned by a query, I tested the query and it is returning the XML with the correct items.. but the code behind has a problem..It reads the first item correctly but then it throws the exception.. I am not sure what is wrong (The exception happens the second time it attempts to go through the WHILE loop. See code below

 // Create Instance of Connection and Command Object开发者_如何转开发
        SqlConnection myConnection = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["myConnection"].ConnectionString);
        SqlCommand myCommand = new SqlCommand("GetItemsXML", myConnection);

        // Mark the Command as a SP
        myCommand.CommandType = CommandType.StoredProcedure;

        // Add Parameters to SP
        SqlParameter parameterPortalID = new SqlParameter("@TheID", SqlDbType.Int, 4);
        parameterPortalID.Value = portalID;
        myCommand.Parameters.Add(parameterPortalID);

        SqlParameter parameterKeywords = new SqlParameter("@myWords", SqlDbType.VarChar, 4000);
        parameterKeywords.Value = myWords;
        myCommand.Parameters.Add(parameterWords);



        // Execute the command
        myConnection.Open();
        SqlDataReader reader = myCommand.ExecuteReader(CommandBehavior.CloseConnection);

        string xmlOut = "";

        while (reader.Read()) //SECOND ITERATION THROWS (Invalid attempt to read
                              // when reader is closed)
        {
            xmlOut = xmlOut + reader[0].ToString();
        }

        xmlOut = "<MyItemsList>" + xmlOut + "</ZMyItemsList>";

        reader.Close();
        myConnection.Close();

        return xmlOut;
    }

It may have something to do with the fact that the first ittereation would be reader[0] but surely the second itteration will be reader[1], therefore you want to use

 reader.GetString(0)

instead of

 reader[0].ToString();

Why you using reader[0].ToString(); this will fetch your first record and give eror on second iteration. Use below instead

reader["ColumnsName"].ToString();