handleScrollTop(){
  window.scrollTo(0, 0);  
}

const urlParams = new URL(window.location.href);
urlParams.searchParams.has("topic") === true; // true
urlParams.searchParams.get("topic") === "api"; // true
urlParams.searchParams.getAll("topic"); // ["api"]
urlParams.searchParams.get("foo") === ""; // true
urlParams.searchParams.append("topic", "webdev");
urlParams.searchParams.toString(); // "q=URLUtils.searchParams&topic=api&topic=webdev"
urlParams.searchParams.set("topic", "More webdev");
urlParams.searchParams.toString(); // "q=URLUtils.searchParams&topic=More+webdev"
urlParams.searchParams.delete("topic");
urlParams.searchParams.toString(); // "q=URLUtils.searchParams"

let arr = ['1','2','3'];
arr.split(',').map(Number);