sample: get all elements which have id attribute

by sii_side

HTML

<div id="01"></div>
<div id="02"></div>
<div id="03"></div>
<div id="04"></div>
<p id="05"></p>
<ul>
  <li id="06"></li>
  <li></li>
  <li></li>
  <li id="07"></li>
</ul>

JavaScript

var elm = document.querySelectorAll("[id]");
console.log(elm.length);