Complex DataBinding accepts as a data source either an IList or an IListSource

Question

I try to extract information the following Bussines rule: public IDataReader GetLista() { string query = "SELECT nombre, telefono FROM Shen.BusLogic.Resume"; OqlCommand cmd = new OqlCommand(query); return cmd.ExecuteReader(); } and I try to used of this way: private void btnConsulta_Click(object sender, System.EventArgs e) { Resume consulta = new Resume(); dgLista.DataSource = consulta.GetLista(); } When appear the following message somebody can help me? : An unhandled exception of type 'System.Exception' occurred in system.windows.forms.dll Additional information: Complex DataBinding accepts as a data source either an IList or an IListSource. I appreciate your help, and excuse me for may english.