两个具有相同变量的foreach循环在html中不起作用 - 在slim framework php中使用twig

Question

I'm trying in my code to build a list of courses in an html file (using twig) - but the thing is - I need to use it twice. Once to get the list (and that obviously worked), and once to create a form with multiple checkboxes running in another for loop. I read that the 'unset' function can fix this problem - but it says in doesn't exist in Twig. here's my code:

{% for course in courses %}
   <a href="/course/{{course.id}}">
    <div id="info-box">
    <img src="/views/{{course.image_link}}" alt="" width=95>
    <p style="margin-left: 1rem;">{{course.name}}</p>
    </div>  
   </a>
{% endfor %}

and then I need to write a form:

<form>

    {% for course in courses %}
         <input type="checkbox" name="course" value={{course.id}}>{{course.name}}           
    {% endfor %}
</form>

The second loop doesn't work. I'd love for some help please! :)

and the courses variable comes from a different index file that sends it to an html file.

Answer 1

I'm not sure why u only can use twig as it would be better to fetch the result in actual array than rather passing the PDOStatement.

The reason u can only foreach the collection once is because PDOStament is a forward-only result set. This means you can only get the data from this object once.

To resolve this issue in twig this would mean u need to build an array first and then use that array to display your html

{% set courses_array = [] %}
{% for course in courses %}
    {% set courses_array = courses_array | merge([course]) %}
{% endfor %}

---

It sure is better to do this in PHP, rather then in twig

<?php
    $stmt = $pdo->prepare('SELECT * FROM courses');
    $stmt->execute();

    $courses = $stmt->fetchAll(PDO::FETCH_ASSOC);
    $twig->render('courses.twig', [ 'courses' => $courses, ]);

---

Another solution would be to do the fetch inside twig, to access a constant you can use the function constant

{% set courses_array = courses.fetchAll(constant('PDO::FETCH_ASSOC')) %}

note: I did not test the last solution