html - CSS pseudo elements in select tag options in Internet Explorer

Question

I'm trying to add some CSS ::before content to the <option> tags of a <select multiple> depending on if the option is selected or not.

The below is currently working fine in Chrome & FF, but I'm having issues in IE11.

select > option::before {
  display: inline-block;
  width: 10em;
}
select > option:checked::before {
  content: "SELECTED: ";
}
select > option:not(:checked)::before {
  content: "excluded: " ;
}

<select multiple>
  <option value="1" selected="selected">1</option>
  <option value="2" selected="selected">2</option>
  <option value="3" selected="selected">3</option>
  <option value="4" selected="selected">4</option>
  <option value="5" selected="selected">5</option>
</select>

Answer 1

First Lets get one thing straight we can't create what you desire in IE because it doesn't allow anything other than <option>,<optgroup> tags inside a <select> box.

This is much of a workaround I can get using CSS only method in my opinion. If you prefer script there are plenty alternatives even select2 is one of the most used plugin for this type of customizations.

I Have used [type="checkbox"] for attain this result

jQuery is only being used to show the value.

var multyVal = [];
$('.multiple input[type="checkbox"]').each(function() {
  if ($(this).is(':checked')) {
    var Tval = $(this).val();
    multyVal.push(Tval);
  }
});

console.log($('select').val(), multyVal);

select>option::before {
  display: inline-block;
  width: 10em;
}

select>option:checked::before {
  content: "SELECTED: ";
}

select>option:not(:checked)::before {
  content: "excluded: ";
}

.multiple {
  height: 60px;
  display: inline-block;
  overflow-y: scroll;
  background: #d4d4d4;
  width: 10em;
  border: 1px solid #999;
  margin-left: 10px;
}

.multiple [type="checkbox"] {
  display: none;
}

.multiple label {
  width: 100%;
  float: left;
  font-size: 13px;
  text-align: right;
  background: #fff;
}

.multiple label::before {
  display: inline-block;
  float: left;
  font-family: arial, san-sarif;
  font-size: 11px;
}

.multiple [type="checkbox"]:checked+label::before {
  content: "SELECTED: ";
}

.multiple [type="checkbox"]:checked+label {
  background: #666;
  color: #fff;
}

.multiple [type="checkbox"]:not(:checked)+label::before {
  content: "excluded: ";
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>


<select multiple>
  <option value="1" selected="selected">1</option>
  <option value="2" selected="selected">2</option>
  <option value="3" selected="selected">3</option>
  <option value="4" >4</option>
  <option value="5" >5</option>
</select>


<div class="multiple">
  <input type="checkbox" name="multiple" value="1" id="rad1" checked="checked">
  <label for="rad1">1</label>

  <input type="checkbox" name="multiple" value="2" id="rad2" checked="checked">
  <label for="rad2">2</label>

  <input type="checkbox" name="multiple" value="3" id="rad3" checked="checked">
  <label for="rad3">3</label>

  <input type="checkbox" name="multiple" value="4" id="rad4">
  <label for="rad4">4</label>

  <input type="checkbox" name="multiple" value="5" id="rad5">
  <label for="rad5">5</label>
</div>