问循环选定内容中的所有选项，并将该值添加到选项名称

EN

const options = document.querySelectorAll('.attribute_taxonomy option');

options.forEach(o => {
  const currentValue = o.getAttribute('value');
  o.innerHTML = `Course Date - ${currentValue}`;
});

<select name="attribute_taxonomy" class="attribute_taxonomy">

<option value="pa_course-date-aromatherapy">Course Date</option>
<option value="pa_course-date-basic-colouring">Course Date</option>
<option value="pa_course-date-body-wraps">Course Date</option>
<option value="pa_course-date-brow-tinting">Course Date</option>
<option value="pa_course-date-cold-fusion">Course Date</option>     

</select>

return valueList.map(v => {
    if(v === "pa_course-date") {
        return <option value={"Course Date" + v}>{"Course Date" + v}</option>
    }
})

$(document).ready(function(){
	$("#select>option").each(function(){
  	$(this).text(this.text + ' - ' + this.value)
  })
})

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<select id="select">
  <option value="pa_course-date-aromatherapy">Course Date</option>
  <option value="pa_course-date-basic-colouring">Course Date</option>
  <option value="pa_course-date-body-wraps">Course Date</option>
  <option value="pa_course-date-brow-tinting">Course Date</option>
  <option value="pa_course-date-cold-fusion">Course Date</option>     
</select>