dropdown with multiple

You could also use this.

PHP Code:

<?= form_multiselect('dpd[]', ['1' => 'First', '2' => 'Second', '3' => 'third', '4' => 'fourth',], '2', "class = 'form-control'"); ?>

Thank you, but what is the difference between an example taken from the documentation where the classical array record is used and the reduced record of the array from yours?