How to know what is selected in "select" JS?

Question

JavaScript

Hello,
My django generates the following code:

<select name="docorderproduct_set-0-pack" id="id_docorderproduct_set-0-pack">
  <option value="" selected>---------</option>
  <option value="1">Мигдаль 1 кг </option>
</select>

And my JS code always returns None!

pack = document.getElementById("id_docorderproduct_set-0-pack").selectedOptions[0].value

And it doesn't matter which item I select in the dropdown list :(

Answer 1

Where is the script loaded? In HEAD or At the end of body ?