How to get all options of a select using jQuery on its class, not ID?

Question

I learned from the famous example how to do this using the ID and I like this solution most of all:

var options = $('#selectBox option');

var values = $.map(options ,function(option) {
    return option.value;
});

I have many repeating blocks in a separate containers like this:

<div class="section">
  <label><input type="checkbox" name="A" value="2" class="factor-checkbox">A</label>


  <select class='helperBox' id='helperBox' >
        <option val='AB'>AB</option>
        <option val='BCD'>BCD</option>
        <option val='C'>C</option>
        <option val='AD'>AD</option>

      </select>
  <label>Result <input type="text" value="10" class="result" ></label>

</div>

<div class="section">
  <label><input type="checkbox" name="A" value="2" class="factor-checkbox">A</label>

  <select  class='helperBox'>
        <option val='B'>B</option>
        <option val='BD'>BD</option>
        <option val='AC'>AC</option>
        <option val='C'>C</option>
      </select>
  <label>Result <input type="text" value="20" class="result" ></label>

</div>

and the following function works:

function loadCombos($section) {
    var $section = $(this).closest(".section");
    //var $combos = $section.find('.helperBox');
    var options = $('#helperBox option');

    var combos = $.map(options,function(option) {
    return option.value;
    });

    console.log(combos);

    return combos;

  }

but only for one helperBox, obviously. How to make it work for many in each section. so that combos arrays are different in different sections ?

Answer 1

You can use the scope for it like (based on assumption that this inside loadCombos here refers to a button inside section div):

function loadCombos() {
  var $section = $(this).closest(".section");
  var $combos = $section.find('.helperBox'); //<-- only select in this section
  var options = $combos.find('option');      //<-- only options of current select
  var combos = $.map(options, function(option) {
    return option.value;
  });

  console.log(combos);
  return combos;
}

Answer 2

IDs are meant to be unique in CSS. You either change the ID to classes or have separate IDs and have a common classname.

<div id="helperbox1" class="helperbox"></div>
<div id="helperbox2" class="helperbox"></div>

or use two classes like

 <div class="helperbox b1"></div>