在Codeigniter中刷新具有不同数据值的视图

Question

Initially when my view loads, it should display the first question and answer. When press the next button I need to pass next value to the model and get the second question and answer, and if next button is clicked again it should display the third question and answer. The next button should be clickable until the last question appears. I have the following code:

Model

function getNextQuestions($quizID,$qusNo) {

        $check = "SELECT * FROM question WHERE quiz_id = '$quizID' AND id='$qusNo'";
        $query = $this->db->query($check);

        if ($query->num_rows() > 0) {
            return $query->result();
        } else {
            return NULL;
        }
    }

Controller

public function index()
    {
        $this->load->model('Model_questions');

        $quizId = $_POST['quizID_click'];

        $data['questions'] = $this->Model_questions->getNextQuestions($quizId,"1");

        $this->load->view('question_view', $data);
}

public function displayNextQuestions()
    {
        $this->load->model('Model_questions');

        $qusId = $_POST['question_nextClick'];

        $data['questions'] = $this->Model_questions->getNextQuestions($quizId,$qusId);

        $this->load->view('question_view', $data);
}

View

<div id="body">

        <?php


            echo $questions[0]->question . "<br>" 
                    . $questions[0]->choice1 . "<br>" 
                    . $questions[0]->answer. "<br>";
                echo '<form action="/Test/index.php/question_controller/displayNextQuestions" method="POST">                
                        <input type="submit" value="Next">
                        <input type="hidden" name="question_nextClick" value="2" />
                    </form>';

        ?>

I didn't get the output that i need, what are the modifications that i should do. Please help me.

Answer 1

The Model looks good. Revised answer to revised question.

Note that I have included the whole controller this time and load the database in the constructor instead of in each function. You alway use the model so take care of it with one line of code.

Controller

<?php
defined('BASEPATH') OR exit('No direct script access allowed');

class Quest_controller extends CI_Controller
{
  function __construct()
  {
    parent::__construct();
    $this->load->database();
    $this->load->model('Model_questions');
  }

  public function index()
  {
    /* 
    Rather than declare and initialize a bunch of different variables 
    only to reassign them to a structure passed to the view we use 
    that structure (`$data`) all the way through. 
    */

    $data["quizId"] = $_POST['quizID_click'];
    //since this is the first time here we set question_num = 1
    $data['question_num'] = 1;
    $data['questions'] = $this->model_questions->getNextQuestions($data["quizId"],
      "1");
    $this->load->view('question_view', $data);
  }

  public function displayNextQ()
  {
    $data['quizId'] = $_POST['quizId'];

    //Notice how we increment the question number.
    //The new number gets sent to the new view
    $data['question_num'] = $_POST['question_num'] + 1;

    $data['questions'] = $this->model_questions
      ->getNextQuestions($data['quizId'], $data['question_num']);

    //if the model returns null then the quiz is done
    if(!isset($data['questions']))
    {
      $this->load->view('test_done_view');
    }
    else
    {
      $this->load->view('question_view', $data);
    }
  }
}

View

Notice how we set the values of the hidden inputs. Those values will be returned in the $_POST array for use by displayNextQ() on the next submit.

In case you don't know, this <?= $quizId; ?> is a shorthand way to write <?php echo $quizId; ?>

<div id="body">
  <?php
  echo $questions[0]->question."<br>".$questions[0]->answer."<br>";
  ?>
  <form action="/testApp/index.php/quest_controller/displayNextQ" method="POST">                
    <input type="hidden" name="quizId" value="<?= $quizId; ?>" />
    <input type="hidden" name="question_num" value="<?= $question_num; ?>" />
    <input type="submit" value="Next">
  </form>
</div>