how to set data-id value for a button using attr() jquery code example

Example 1: jquery get data attribute value

/* html */
<a data-id="123">link</a>

/* js */
$(this).attr("data-id") // returns string "123"

$(this).data("id") // returns number 123 (jQuery >= 1.4.3 only)

Example 2: javascript get data-id attribute

//get data-id attribute in plain Javascript
var element = document.getElementById('myDivID');
var dataID = element.getAttribute('data-id');

//get data-id using jQuery
var dataID = $('myDivID').data('data-id');