c# error to call stored proc in dll

[niketa]

hello
i m making dll class for stored procedure as...help me to correct it...my boss said that i m missing parameter values to return but i m not getting anything to correct it...
public class transactionService
{
SqlConnection cs;

private void OpenConnection()
{
cs = new SqlConnection();
cs.ConnectionString = "Data Source=IRIS-CSG-174;Initial Catalog=library_system;Integrated Security=True";
cs.Open();
}
public membership_details calculatefine()
{
OpenConnection();
SqlCommand cmd = new SqlCommand();
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "Exec member_fine_detail";
cmd.Parameters.Add(new SqlParameter("member_id", SqlDbType.Int));


membership_details myObjec = new membership_details();
cmd.ExecuteNonQuery();
SqlDataReader sdr = cmd.ExecuteReader();
myObjec.fine_per_day = 0;

return myObjec;
help me to correct this code...i m trying to get fne_per_day as per member_id and after this reference is adding to return form in project from that according to member_id fine_per_day is calculated...as the creteria is like member_id=5,membership_desc=silver,gol,platinum,fineperday=30or 20or10