Bind 2 DropDownList in one page asp.net

protected void Page_Load(object sender, EventArgs e)
  {
      BindDropDown(ddl1, "SP_1", "textfield", "valuefield");
      BindDropDown(ddl2, "SP_2", "textfield", "valuefield");
  }
  private void BindDropDown(DropDownList dl, string spName, string dataTextField, string dataValueField)
  {
      SqlConnection _cn = new SqlConnection(System.Web.Configuration.WebConfigurationManager.ConnectionStrings["behtopConnectionString"].ConnectionString);
      SqlCommand _cmd = new SqlCommand(spName, _cn);
      _cmd.CommandType = CommandType.StoredProcedure;
      _cn.Open();
      SqlDataReader _dr = _cmd.ExecuteReader();
      if (_dr.HasRows)
      {
          dl.DataSource = _dr;
          dl.DataTextField = dataTextField;
          dl.DataValueField = dataValueField;
          dl.DataBind();
      }
      _cn.Close();
  }