get data in javascript from html5 code example

Example 1: html javascript find data attribute

//javascript get html data attribute
<button data-id="1" >Click</button>
<button data-id="2" >Click</button>
<button data-id="3" >Click</button>
const btns=document.querySelectorAll('button[data-id]');
[...btns].forEach(btn => console.log(btn.getAttribute('data-id')))

Example 2: get data attribute javascript

// <div id="element" data-name="john"></div>

const el = document.querySelector('#element')
el.dataset.name // 'john'