Database values in textbox if select Combobox....no output gnerating

try
            {
               
               
                con.Open();
                string search = "select Amount from Mess_Plans Where PlanName='" + comboBox1_SelectPlan.Text + "' ;";
                OleDbCommand cmd1 = new OleDbCommand(search, con);
                String i = cmd1.ExecuteReader();
                MessageBox.Show("slected" +i);
               
            }
            catch(Exception e2)
            {
                MessageBox.Show(e2.ToString());
            }
            finally
            {
                con.Close();
            }