JSFiddle - React, Tailwind, and code Playground
HTML
<button id="some_id1"></button>
<button id="some_id2"></button>
<button id="some_id3"></button>
<button id="some_id4"></button>
<button id="some_id5"></button>
JavaScript
var buttons = document.getElementsByTagName("button");
var buttonsCount = buttons.length;
for (var i = 0; i <= buttonsCount; i += 1) {
buttons[i].onclick = function(e) {
alert(this.id);
};
}