Answers for "get data element value jquery by class"

jquery get element by class and data attribute

$('.slide-link[data-slide="0"]').addClass('active');

jquery get data attribute value by class

//get the result as array
<option value="<?php echo $value['id']; ?>" data-count="5">
</option>

var data = $('.myclass').map(function() {
    return $(this).data('optionid');
}).get();