Javascript - Copy content from a <span> to clipboard by clicking a <button>

Question

I am creating a CPF generator, which when the person generates, appears an option "Copy", but I would like to know how to implement the functionality of copying the content that is presented.

Example HTML code:

<span id="numerosx">56262662</span>
<button id="btcopiar">COPIAR</button>

Note: Pure Javascript.

Answer 1

Behold:

document.querySelector("button").onclick = function() {
    var element= document.getElementById('numerosx');
    var range = document.createRange();
    range.selectNode(element);
    window.getSelection().addRange(range);
    document.execCommand("copy");
};

<span id="numerosx">56262662</span>
<button id="btcopiar">COPIAR</button>