Required Elements
Required element
Html
<div class="control-group">
<form>
  <label for="select-beast">Beast:</label>
  <select id="select-beast" required class="demo-default"
    placeholder="Select a person..." name="beast">
    <option value="">Select a person...</option>
    <option value="4">Thomas Edison</option>
    <option value="1">Nikola</option>
    <option value="3">Nikola Tesla</option>
    <option value="5">Arnold Schwarzenegger</option>
  </select>
    <button type="submit">Submit</button>
</form>
</div>
Javascript
$('#select-beast').selectize({
  create: true,
  sortField: {
    field: 'text',
    direction: 'asc'
  }
});