Question

How can I check if a user has selected something from a <select> field in HTML?

I see <select> doesn’t support the new required attribute… do I have to use JavaScript then? Or is there something I’m missing? :/

Answer 1

Mandatory: Have the first value empty – required works on empty values

Prerequisites: correct html5 DOCTYPE and a named input field

<select name="somename" required>
<option value="">Please select</option>
<option value="one">One</option>
</select>

As per the documentation (the listing and bold is mine)

The required attribute is a boolean
attribute.
When specified, the user
will be required to select a value
before submitting the form.

If a select element

• has a required attribute specified,
• does not have a multiple attribute specified,
• and has a display size of 1 (do not have SIZE=2 or more – omit it if not needed);
• and if the value
  of the first option element in the
  select element’s list of options (if
  any) is the empty string (i.e. present as value=""),
• and that
  option element’s parent node is the
  select element (and not an optgroup
  element),

then that option is the
select element’s placeholder label
option.