# Konami Code in JavaScript
**URL:** https://forum.kirupa.com/t/konami-code-in-javascript/640851
**Category:** web dev
**Created:** [October 15, 2019, 5:21am UTC](https://forum.kirupa.com/t/konami-code-in-javascript/640851 "2019-10-15T05:21:22Z")
**Posts on this page:** 2
**Page:** 1
With Fortnite [giving users a mini-game](https://twitter.com/FortniteBR/status/1183454945808453634) if they enter the Konami code while seeing the black hole, it seems like a good time to show this snippet that shows how to detect this code using JavaScript:
```
Konami Code!
Konami Code
Click here to give the page focus and enter the Konami code!
```
I’ll write a tutorial eventually on it, but it uses techniques showed in the [Working With the Keyboard](https://www.kirupa.com/html5/keyboard_events_in_javascript.htm) and [Timers](https://www.kirupa.com/html5/timers_js.htm) tutorials.
Cheers,
Kirupa 😛
---
This is more of a matching game where you have to match the sequence to clear lines, each line being a collection of the keys you’ve used between hitting ENTER. But you start off with the first line being the Konami code, so it applies 😉
```javascript
const replacements = {
"ArrowUp": "⬆️",
"ArrowDown": "⬇️",
"ArrowLeft": "⬅️",
"ArrowRight": "➡️",
};
const root = document.body.appendChild(document.createElement("div"));
function newLine() {
return root.appendChild(document.createElement("p"));
}
function addKey(key) {
root.lastElementChild.innerHTML += ``;
}
function clearMatches() {
const curr = root.lastElementChild;
const prev = curr.previousElementSibling;
if (prev?.innerHTML === curr.innerHTML) {
newLine();
setTimeout(() => (curr.remove(), prev.remove()), 500);
}
}
window.onkeyup = ({ key }) => {
if (key === "Enter") {
if (root.lastElementChild.childElementCount) newLine();
return;
}
addKey(key);
clearMatches();
}
newLine();
addKey("ArrowUp");
addKey("ArrowUp");
addKey("ArrowDown");
addKey("ArrowDown");
addKey("ArrowLeft");
addKey("ArrowRight");
addKey("ArrowLeft");
addKey("ArrowRight");
addKey("b");
addKey("a");
newLine();
```
P.S. You win nothing by clearing all the lines 🙃
[JSFiddle link](https://jsfiddle.net/xvLphtaq/1/)