SqlDataReader to CSV

private static void SqlDataReaderToCSV(SqlDataReader reader, string path)
{
    using (StreamWriter writer = new StreamWriter(path))
    {
        string[] headers = new string[reader.FieldCount];
        for (int i = 0; i < reader.FieldCount; i++)
        {
            headers[i] = string.format("{0}", reader.GetName(i));
        }
        writer.WriteLine(string.Join(",", headers));

        while (reader.Read())
        {
            string[] row = new string[reader.FieldCount];
            for (int i = 0; i < reader.FieldCount; i++)
            {
                row[i] = string.format("{0}", reader.GetValue(i));
            }
            writer.WriteLine(string.Join(",", row));
        }
    }
}