jquery data attribute

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

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

$(this).data("number") // returns number 123 (jQuery >= 1.4.3 only)const dataId = $('#elementId').attr("data-id");<a data-id="123">link</a>


var id = $(this).data("id"); // Will set id to 123data attribute in jquery 

For setting attribute data to the element
Html
<p id="assign">Assigning data attribute</p>
jquery
$("#assign").data("title","firstparagraph");

Output:
<p id="assign" data-title="firstparagraph">Assigning data attribute</p>

For getting attribute data from the element
Html
<p id="assign" data-title="firstparagraph">Assigning data attribute</p>
jquery
console.log($("#assign").data("title"));
console.log($("#assign").data());

Output:
firstparagraph
{ title: firstparagraph }