to get data from a tag code example

Example 1: 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');

Example 2: data id tag

var dataId = $(this).attr("data-id");