JSFiddle - React, Tailwind, and code Playground

HTML

<a href="ajax.php?search=text&type=xxx&PAGEN_1=2">ссылка</a>

JavaScript

var link = document.querySelector('a');
link.addEventListener('click', getParam, false);

function getParam(e){
  e.preventDefault();
  console.log(getURLParam(e.toElement.search, 'PAGEN_1')); // тут вводим имя параметра
}
function getURLParam(target, name) {
  return decodeURI(target.replace(new RegExp("^(?:.*[&\\?]" + encodeURI(name).replace(/[\.\+\*]/g, "\\$&") + "(?:\\=([^&]*))?)?.*$", "i"), "$1"));
}