jquery get data attribute value by class

1/* html */
2<a data-id="123">link</a>
3
4/* js */
5$(this).attr("data-id") // returns string "123"
6
7$(this).data("id") // returns number 123 (jQuery >= 1.4.3 only)

1$('.slide-link[data-slide="0"]').addClass('active');
2

1//get the result as array
2<option value="<?php echo $value['id']; ?>" data-count="5">
3</option>
4
5var data = $('.myclass').map(function() {
6    return $(this).data('optionid');
7}).get();

1$("ul[data-slide='" + current +"']");
2