getting data from sql server

public static void dispaly_functions_module_role(string proc_fun, int mod_int, int rol_int, CheckedListBox c1)
        {
            try
            {
                int count = 0;
                int count1 = 0;
                string sql_string = ("Data Source=sdggdfgdfgdfg;Initial Catalog=GCERP_SEC;User Id=sdfgdsfg;Password=fgsdfg");
                SqlConnection conn = new SqlConnection(sql_string);
                SqlCommand command = new SqlCommand(proc_fun, conn);
                conn.Open();
                command.CommandType = CommandType.StoredProcedure;
                command.Parameters.AddWithValue("@mid", mod_int);
                command.Parameters.AddWithValue("@rid", rol_int);
                SqlDataReader rdr = command.ExecuteReader();

                if (rdr.HasRows)
                {
                    StringBuilder sb = new StringBuilder();
                    string a;
                    while (rdr.Read())
                    {
                        sb.Append(((int)rdr[mod_int]));
                        sb.Append(((int)rdr[rol_int]));
                        sb.Append("\n");
                        a = sb.ToString().Trim();
                        c1.Items.Add(a);
                       // Items.Insert(count1, a);
                        sb.Length = 0;
                        count1++;
                    }

                }
                else
                {
                    if (count1 != 0)
                        MessageBox.Show(" your data is saved");
                    else
                        MessageBox.Show("not found");
                }

                rdr.Close();
                command.ExecuteNonQuery();
                count++;
                conn.Close();
                conn.Dispose();

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                MessageBox.Show("Error in database connection");
            }
        }